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Sample records for bioavailable testosterone levels

  1. Monitoring testosterone levels in testosterone-treated men.

    PubMed

    Winters, Stephen J

    2016-01-01

    Dose adjustment with transdermal testosterone preparations should recognize the variability of serum total testosterone levels between applications and over the course of 24 h. Dose adjustments are also made difficult by between-laboratory assay variability. Low SHBG with obesity and diabetes lowers the total testosterone level, and free or bioavailable testosterone may prove to be a better choice for monitoring the progress and dosing of testosterone-treated men with adult onset hypogonadism.

  2. Physiological levels of testosterone kill salmonid leukocytes in vitro

    USGS Publications Warehouse

    Slater, C.H.; Schreck, C.B.

    1997-01-01

    Adult spring chinook salmon (Oncorhynchus tshawytscha) elaborate high plasma concentrations of testosterone during sexual maturation, and these levels of testosterone have been shown to reduce the salmonid immune response in vitro. Our search for the mechanism of testosterone's immunosuppressive action has led to the characterization of an androgen receptor in salmonid leukocytes. In the present study we examined the specific effects that testosterone had on salmonid leukocytes. Direct counts of viable leukocytes after incubation with and without physiological levels of testosterone demonstrate a significant loss of leukocytes in cultures exposed to testosterone. At least 5 days of contact with testosterone was required to produce significant immunosuppression and addition of a 'conditioned media' (supernatant from proliferating lymphocytes not exposed to testosterone) did not reverse the immunosuppressive effects of testosterone. These data lead us to conclude that testosterone may exert its immunosuppressive effects by direct action on salmonid leukocytes, through the androgen receptor described, and that this action leads to the death of a significant number of these leukocytes.

  3. Serum Testosterone Levels in Sex Offenders.

    ERIC Educational Resources Information Center

    Gurnani, Prem D.; Dwyer, Margretta

    1986-01-01

    Reports that with the increase in diagnosis of offenders across the nation, physicians and psychiatric personnel need to be aware of low testosterone as a possible indicator of hypo-sexuality and possible concurrent offending behavior. (Author/ABB)

  4. An exploration of testosterone levels in patients with bipolar disorder

    PubMed Central

    Wooderson, Sarah C.; Gallagher, Peter; Watson, Stuart

    2015-01-01

    Background Testosterone influences well-being, mood and cognition and may play a role in the pathophysiology of bipolar disorder. Aim To examine testosterone levels in patients with bipolar disorder compared with healthy controls. Method We examined baseline total testosterone levels and current depression scores in male and female patients with bipolar disorder and mild to moderate depression and healthy controls. Results A significant interaction between diagnosis and gender was observed (F(2,97)=9.791, P=0.002). Testosterone levels were significantly lower for male patients with bipolar disorder compared with male controls (P=0.001). Women with bipolar disorder had significantly higher testosterone levels than female controls (P=0.03). Conclusions Disturbances in testosterone levels may represent an important neurobiological abnormality in bipolar disorder and may differ by gender. If these findings are confirmed, the use of gender appropriate treatment strategies for the normalisation of testosterone levels in bipolar disorder depression should be further explored. Declaration of interest None. Copyright and usage © The Royal College of Psychiatrists 2015. This is an open access article distributed under the terms of the Creative Commons Non-Commercial, No Derivatives (CC BY-NC-ND) licence. PMID:27703738

  5. The effect of food composition on serum testosterone levels after oral administration of Andriol® Testocaps®

    PubMed Central

    Schnabel, Peter G; Bagchus, Wilma; Lass, Holger; Thomsen, Torben; Geurts, T B Paul

    2007-01-01

    Objective Andriol® Testocaps® is a new oral formulation of testosterone undecanoate (TU) for treatment of hypogonadism. As TU is taken up by the intestinal lymphatic system, both the presence and the composition of food influence the absorption. The aim of this study was to investigate the effect of food composition on the pharmacokinetics of oral TU. Design An open-label, single-centre, four-way crossover study. With a washout period of 6–7 days, 80 mg TU was administered in the morning 5 min after consuming each of four different meals in a randomized order (A: 230 kcal, 0·6 g lipid; B: 220 kcal, 5 g lipid; C: 474 kcal, 19 g lipid; D: 837 kcal, 44 g lipid). Patients Twenty-four postmenopausal volunteers. Measurements Serial blood samples were collected until 24 h after dosing to determine testosterone and dihydrotestosterone (DHT) by gas chromatography-mass spectroscopy (GC-MS). Results The bioavailability of testosterone after a low-calorie meal containing 0·6 g lipid or 5 g lipid was relatively low, the area under the concentration–time curve (AUC0–tlast) for testosterone being 30·7 and 43·5 nmol h/l, respectively. The bioavailability of testosterone after a meal containing 19 g lipid was considerably higher (AUC0–tlast = 146 nmol h/l), whereas increasing the lipid content to 44 g lipid did not further increase the bioavailability of testosterone (AUC0–tlast = 154 nmol h/l). Conclusion Approximately 19 g of lipid per meal efficiently increases absorption of testosterone from oral TU. Therefore, coadministration with a normal rather than a fatty meal is sufficient to increase serum testosterone levels when using oral TU. PMID:17371478

  6. The efficacy, bioavailability and safety of a novel hydroalcoholic testosterone gel 2% in hypogonadal men: results from phase II open-label studies.

    PubMed

    Efros, M; Carrara, D; Neijber, A

    2016-08-01

    Pharmacokinetics, pharmacodynamics and safety of a novel hydroalcoholic testosterone gel 2% (TG) were evaluated in phase II sequential dose escalation studies using 3 application sites (thigh, abdomen and shoulder/upper arm) and 2 application methods. Hypogonadal men (n = 40), 18-75 years, with serum testosterone <300 ng dl(-1) were included in both studies. Study 1 evaluated hand-applied multiple doses of TG 1.25, 2.50 and 3.75 ml (23, 46 and 70 mg of testosterone, respectively), once daily for 10 days to shoulder/upper arm. Study 2 evaluated applicator-applied (TG 1.25, 2.50 and 3.75 ml) versus hand-applied (TG 2.5 ml) doses, once daily for 7 days to shoulder/upper arm. Primary endpoint for both studies was responder rate (Cave testosterone levels between 298 and 1050 ng dl(-1) ). In Study 1 following multiple applications, >70% participants in each group were responders. Dose-dependent increase was observed in PK values for total testosterone, free testosterone and DHT. In Study 2, responder rate was dose proportional: 16.7%, 50.0% and 77.8% responders in TG 1.25, 2.50 and 3.75 ml groups respectively. The bioavailability was highest for the shoulder application. There was a significant improvement in almost all the domains of sexual functioning. Applicator-application was preferred over hand-application by majority of the participants. TG was found to be safe and well tolerated in hypogonadal men.

  7. Testosterone levels and fecundity in the hermaphroditic aquatic snail Lymnaea stagnalis exposed to testosterone and endocrine disruptors.

    PubMed

    Giusti, Arnaud; Ducrot, Virginie; Joaquim-Justo, Célia; Lagadic, Laurent

    2013-08-01

    Endocrine disruptors are known to alter endogenous free and esterified levels of androgenic and estrogenic steroid hormones in aquatic mollusks. The origin of steroids in these animals, however, remains controversial. In the present study, free and esterified testosterone concentrations were measured in the hermaphroditic aquatic gastropod Lymnaea stagnalis exposed to molecules known for their androgenic (testosterone and tributyltin), anti-androgenic (cyproterone-acetate), and estrogenic (chlordecone) properties, by reference to their mode of action in vertebrates. In parallel, snail oviposition and fecundity were followed over a 21-d exposure period. Testosterone exposure resulted in increased esterified testosterone levels, whereas free testosterone concentrations remained stable. In contrast, cyproterone-acetate significantly increased the free form of testosterone with no changes in the esterified form, whereas chlordecone showed a tendency to reduce (though not significantly) esterified testosterone concentrations without changing free testosterone levels. Finally, tributyltin did not alter testosterone homeostasis. The production of egg clutches and eggs was significantly reduced only in the snails exposed to the highest concentrations of chlordecone (19.6 µg/L) and tributyltin (94.2 ng Sn/L). Overall, the present study demonstrates that uptake of testosterone from the exposure medium occurs in L. stagnalis. Moreover, it shows that cyproterone-acetate and, to a lesser extent, chlordecone can alter endogenous testosterone levels in this freshwater snail. However, the relationship between hormonal changes and snail reproduction has not been established. Environ Toxicol Chem 2013;32:1740-1745. © 2013 SETAC.

  8. Sex-Specific Associations between Umbilical Cord Blood Testosterone Levels and Language Delay in Early Childhood

    ERIC Educational Resources Information Center

    Whitehouse, Andrew J. O.; Mattes, Eugen; Maybery, Murray T.; Sawyer, Michael G.; Jacoby, Peter; Keelan, Jeffrey A.; Hickey, Martha

    2012-01-01

    Background: Preliminary evidence suggests that prenatal testosterone exposure may be associated with language delay. However, no study has examined a large sample of children at multiple time-points. Methods: Umbilical cord blood samples were obtained at 861 births and analysed for bioavailable testosterone (BioT) concentrations. When…

  9. Effects of chrysin on urinary testosterone levels in human males.

    PubMed

    Gambelunghe, Cristiana; Rossi, Ruggero; Sommavilla, Marco; Ferranti, Chiara; Rossi, Riccardo; Ciculi, Chiara; Gizzi, Stefania; Micheletti, Alessandra; Rufini, Stefano

    2003-01-01

    The equilibrium of sexual hormones in both sexes is controlled in vertebrates by the enzyme aromatase, a member of the cytochrome P450 superfamily, which catalyzes the conversion of androstenedione and testosterone into estrone and estradiol, respectively. Flavonoids are diphenolic compounds present in whole grains, legumes, fruits, and vegetables that are strongly implicated as protective in coronary heart disease, stroke, and cancer. One flavonoid, chrysin, found in high concentrations in honey and propolis, has been shown to be an inhibitor of aromatase enzyme activity. These foods are often used as supplements, particulary by sportsmen for their energetic and antioxidant properties. The aim of this study was to verify if daily treatment for 21 days with propolis and honey, containing chrysin, would modify urinary concentrations of testosterone in volunteer male subjects. In fact, aromatase inhibition by chrysin could block the conversion of androgens into estrogens with a consequent increase of testosterone, eventually measurable in urine samples. The obtained data did not show alterations of the levels of testosterone in the volunteers after 7, 14, and 21 days of treatment in comparison with baseline values and compared with measurements on the control subjects at the same time. In conclusion, the use of these foods for 21 days at the doses usually taken as oral supplementation does not have effects on the equilibrium of testosterone in human males.

  10. Effects of morphine on testosterone levels in rat C6 glioma cells: modulation by anastrozole.

    PubMed

    Ceccarelli, Ilaria; Rossi, Antonella; Maddalena, Melinda; Weber, Elisabetta; Aloisi, Anna Maria

    2009-10-01

    Rat C6 glioma cells are commonly used to investigate the functions of glial cells. To evaluate the presence of testosterone and its metabolism in rat C6 glioma cells, we cultured them in media with or without the addition of testosterone propionate and anastrozole, a blocker of aromatase, the enzyme needed to transform testosterone into estradiol. The same procedure was repeated with morphine (10 and 100 microM), known to decrease testosterone levels in the brain (in rats) and plasma (in rats and humans). Confluent cells were exposed to the test media for 48 h and then collected. Cell pellets were used to determine testosterone by radioimmunoassay. The C6 cells contained detectable levels of testosterone and the levels increased with the addition of testosterone to the medium. Aromatase blockage by anastrozole increased cellular levels of testosterone regardless of the addition of exogenous testosterone. Both concentrations of morphine dose-dependently decreased testosterone levels in the C6 cells; this effect was also present with the contemporary administration of anastrozole. Our findings show that testosterone is present in rat C6 glioma cells and can be metabolized by aromatase. Moreover, the presence of morphine in the culture medium strongly decreased testosterone, demonstrating that the glia would be a target of the morphine-induced hypogonadal effect.

  11. Salivary testosterone levels in men at a U.S. sex club.

    PubMed

    Escasa, Michelle J; Casey, Jacqueline F; Gray, Peter B

    2011-10-01

    Vertebrate males commonly experience elevations in testosterone levels in response to sexual stimuli, such as presentation of a novel mating partner. Some previous human studies have shown that watching erotic movies increases testosterone levels in males although studies measuring testosterone changes during actual sexual intercourse or masturbation have yielded mixed results. Small sample sizes, "unnatural" lab-based settings, and invasive techniques may help account for mixed human findings. Here, we investigated salivary testosterone levels in men watching (n = 26) versus participating (n = 18) in sexual activity at a large U.S. sex club. The present study entailed minimally invasive sample collection (measuring testosterone in saliva), a naturalistic setting, and a larger number of subjects than previous work to test three hypotheses related to men's testosterone responses to sexual stimuli. Subjects averaged 40 years of age and participated between 11:00 pm and 2:10 am. Consistent with expectations, results revealed that testosterone levels increased 36% among men during a visit to the sex club, with the magnitude of testosterone change significantly greater among participants (72%) compared with observers (11%). Contrary to expectation, men's testosterone changes were unrelated to their age. These findings were generally consistent with vertebrate studies indicating elevated male testosterone in response to sexual stimuli, but also point out the importance of study context since participation in sexual behavior had a stronger effect on testosterone increases in this study but unlike some previous human lab-based studies.

  12. Neither testosterone levels nor aggression decrease when the male Mongolian gerbil (Meriones unguiculatus) displays paternal behavior.

    PubMed

    Juana, Luis; Bárbara, Vázquez-Gaytán; Martín, Martínez-Torres; Agustín, Carmona; Guillermo, Ramos-Blancas; Guadalupe, Ortíz

    2010-03-01

    The first studies that correlated mammalian paternal behavior and testosterone levels indicated that the concentration of this steroid hormone decreases when males exhibit paternal care. However, recent studies have also shown that testosterone levels do not decrease when males display paternal behavior. In this study, we measured testosterone levels in plasma throughout the reproductive cycle of the Mongolian gerbil. Testosterone concentrations were correlated with paternal care as well as aggression. We also examined whether there is a trade-off between paternal behavior and aggression in this mammal. Our results show that Mongolian gerbil testosterone levels do not decrease when the males give paternal care. Likewise, male Mongolian gerbils exhibit high levels of aggression while displaying paternal behavior, indicating that there is no trade-off between aggression and paternal behavior. More studies are needed to determine whether testosterone is involved in the regulation of paternal behavior in this rodent.

  13. Maternal personality and reproductive ambition in women is associated with salivary testosterone levels.

    PubMed

    Deady, D K; Smith, M J Law; Sharp, M A; Al-Dujaili, E A S

    2006-01-01

    Previous research has linked testosterone levels with sex-specific personality traits within women. The present study investigates the relation between salivary testosterone levels and specifically maternal personality traits in healthy adult women. Twenty-seven young women completed the Bem Sex Role Inventory (BSRI). Additional questions were asked about maternal personality (importance of having children, self-rated maternal/broodiness), reproductive ambition (ideal number of children, ideal own age at first child) and career orientation (importance of having career). Higher circulating testosterone levels were associated with lower scores on measures of maternal personality and reproductive ambition. There was no relation of career orientation with testosterone. A median split on BSRI masculinity revealed high scorers had higher testosterone levels than low scorers. There was no relation of BSRI femininity with testosterone. Results suggest maternal tendencies may be partly androgen driven.

  14. Enhanced transdermal bioavailability of testosterone propionate via surfactant-modified ethosomes

    PubMed Central

    Meng, Shu; Chen, Zaixing; Yang, Liqun; Zhang, Wei; Liu, Danhua; Guo, Jing; Guan, Yanmin; Li, Jianxin

    2013-01-01

    The current investigation aimed to evaluate the transdermal potential of novel testosterone propionate (TP) ethosomes and liposomes prepared by surfactant modification. The effect of hexadecyl trimethyl ammonium bromide and cremophor EL-35 on the particle size and zeta potential of the prepared vesicles was investigated. The entrapment efficiency and stability, as well as in vitro and in vivo skin permeation, were studied with the various techniques, such as differential scanning calorimetry, confocal laser scanning microscopy, transmission electron microscopy, dynamic light scattering, and so on. The results indicated that the ethosomes were defined as spherical, unilamellar structures with low polydispersity (0.100 ± 0.015) and nanometric size (156.5 ± 3.5 nm). The entrapment efficiency of TP in ethosomal and liposomal carriers was 92.7% ± 3.7% and 64.7% ± 2.1%, respectively. The stability profile of the prepared TP ethosomal system assessed for 120 days revealed very low aggregation and very low growth in vesicular size. TP ethosomes also provided an enhanced transdermal flux of 37.85 ± 2.8 μg/cm2/hour and a decreased lag time of 0.18 hours across mouse skin. The skin permeation efficiency of the TP ethosomes as further assessed by confocal laser scanning microscopy revealed enhanced permeation of rhodamine red-loaded formulations to the deeper layers of the skin (260 μm) than that of the liposomal formation (120 μm). PMID:23990718

  15. Enhanced transdermal bioavailability of testosterone propionate via surfactant-modified ethosomes.

    PubMed

    Meng, Shu; Chen, Zaixing; Yang, Liqun; Zhang, Wei; Liu, Danhua; Guo, Jing; Guan, Yanmin; Li, Jianxin

    2013-01-01

    The current investigation aimed to evaluate the transdermal potential of novel testosterone propionate (TP) ethosomes and liposomes prepared by surfactant modification. The effect of hexadecyl trimethyl ammonium bromide and cremophor EL-35 on the particle size and zeta potential of the prepared vesicles was investigated. The entrapment efficiency and stability, as well as in vitro and in vivo skin permeation, were studied with the various techniques, such as differential scanning calorimetry, confocal laser scanning microscopy, transmission electron microscopy, dynamic light scattering, and so on. The results indicated that the ethosomes were defined as spherical, unilamellar structures with low polydispersity (0.100 ± 0.015) and nanometric size (156.5 ± 3.5 nm). The entrapment efficiency of TP in ethosomal and liposomal carriers was 92.7% ± 3.7% and 64.7% ± 2.1%, respectively. The stability profile of the prepared TP ethosomal system assessed for 120 days revealed very low aggregation and very low growth in vesicular size. TP ethosomes also provided an enhanced transdermal flux of 37.85 ± 2.8 μg/cm(2)/hour and a decreased lag time of 0.18 hours across mouse skin. The skin permeation efficiency of the TP ethosomes as further assessed by confocal laser scanning microscopy revealed enhanced permeation of rhodamine red-loaded formulations to the deeper layers of the skin (260 μm) than that of the liposomal formation (120 μm).

  16. Social modulation of testosterone levels in male black howlers (Alouatta pigra).

    PubMed

    Rangel-Negrín, Ariadna; Dias, Pedro A D; Chavira, Roberto; Canales-Espinosa, Domingo

    2011-01-01

    The influence of social factors on the modulation of male testosterone levels has been demonstrated among several vertebrate species. In addition to sexual activity, parental care and reproductive competition affect testosterone secretion. We examined variations in testosterone levels among male black howlers (Alouatta pigra) in various social contexts. Fecal samples were collected from nine males living in five different groups in the Mexican state of Campeche. The potential for intragroup and extragroup competition varied among the groups. The number of resident males living in the groups was the only variable that significantly explained variations in testosterone levels. Males living in unimale groups had higher testosterone levels; the highest testosterone levels were recorded for males that had experienced a shift from multimale to unimale group compositions. In this species, the probability of being challenged by extragroup males and evicted from the group during immigration events increases when males live in unimale groups. Therefore, our results suggest that male black howlers respond to competition for group membership by increasing their testosterone levels. In this context, testosterone secretion represents an anticipatory response to reproductive conflicts. Therefore, although males living in unimale groups have exclusive access to females, they face higher physiological costs associated with sustaining high testosterone levels for extended time periods.

  17. Testosterone levels in healthy men are related to amygdala reactivity and memory performance.

    PubMed

    Ackermann, Sandra; Spalek, Klara; Rasch, Björn; Gschwind, Leo; Coynel, David; Fastenrath, Matthias; Papassotiropoulos, Andreas; de Quervain, Dominique J-F

    2012-09-01

    Testosterone is a steroid hormone thought to influence both emotional and cognitive functions. It is unknown, however, if testosterone also affects the interaction between these two domains, such as the emotional arousal-induced enhancement of memory. Healthy subjects (N=234) encoded pictures taken from the International Affective Picture System (IAPS) during functional magnetic resonance imaging (fMRI) and underwent a free recall test 10 min after memory encoding. We show that higher endogenous testosterone levels at encoding were associated with higher arousal ratings of neutral pictures in men. fMRI analysis revealed that higher testosterone levels were related to increased brain activation in the amygdala during encoding of neutral pictures. Moreover, endogenous testosterone levels were positively correlated with the number of freely recalled neutral pictures. No such relations were found in women. These findings point to a male-specific role for testosterone in enhancing memory by increasing the biological salience of incoming information.

  18. Correlation between serum testosterone level and concentrations of copper and zinc in hair tissue.

    PubMed

    Chang, Chung Soo; Choi, Jong Bo; Kim, Hae Jin; Park, Sat Byul

    2011-12-01

    Testosterone deficiency is associated with late-onset hypogonadism. Micronutrients including copper (Cu) and zinc (Zn) influence testosterone synthesis. The association between micronutrient concentrations in hair tissue and serum testosterone was studied in Korean men. The subjects were 88 men 40-60 years of age who visited the health promotion center and an outpatient clinic of family medicine at a university hospital from March 2006 to February 2008. Population sociological features of the subjects were acquired by self-administered surveys and interview, height and weight were measured, serum total testosterone was determined in the morning, and Cu and Zn were quantified from hair tissue collected in the morning. Subjects with normal testosterone group had a significantly higher Zn level compared to low testosterone group (P = 0.003). Significant negative correlations were evident between total testosterone and Cu level (r = -0.252, P = 0.022), and the Cu/Zn ratio (r = -0.288, P = 0.008). Normal testosterone is associated with a higher Zn level. Decreased serum testosterone is significantly associated with a high level of Cu and elevated Cu/Zn ratio in hair tissue.

  19. Relations between Prenatal Testosterone Levels and Cognitive Abilities at 4 Years.

    ERIC Educational Resources Information Center

    Finegan, Jo-Anne K.; And Others

    1992-01-01

    Compared children's cognitive abilities at four years and their prenatal amniotic fluid testosterone levels. For girls, prenatal testosterone levels were related in a curvilinear manner to language comprehension and classification abilities, and inversely related to counting and knowledge of number facts. For boys, no relationships were found. (BC)

  20. Supplementation with vitamin D does not increase serum testosterone levels in healthy males.

    PubMed

    Jorde, R; Grimnes, G; Hutchinson, M S; Kjærgaard, M; Kamycheva, E; Svartberg, J

    2013-09-01

    Cross-sectional studies indicate a positive relation between serum 25-hydroxyvitamin D [25(OH)D] and testosterone. It is not known if this relation is causal, which in theory could be in both directions. A cross-sectional population based study was designed with pooled data from 3 vitamin D randomized clinical trials (RCTs) performed in Tromsø with weight reduction, insulin sensitivity, and depression scores as endpoints, and one testosterone RCT in subjects with low serum testosterone (<11.0 nmol/l) and with body composition as endpoint. Serum 25(OH)D and androgens were measured in 893 males in the cross-sectional part, at baseline and after 6-12 months of supplementation with vitamin D 20 000 IU-40 000 IU per week vs. placebo in the vitamin D RCTs (n=282), and at baseline and after one year treatment with testosterone undecanoate 1 000 mg or placebo injections (at baseline and after 6, 16, 28, and 40 weeks) in the testosterone RCT (n=37). In the cross-sectional study, serum 25(OH)D was found to be a significant and positive predictor of serum testosterone. In the vitamin D RCTs, no significant effect on serum total or free testosterone levels was seen, and in the testosterone RCT no significant effect on serum 25(OH)D was seen. This was unchanged in sub-analyses in subjects with low serum 25(OH)D (or testosterone) levels. In conclusion, in subjects without significant vitamin D deficiency, there is no increase in serum testosterone after high dose vitamin D supplementation. Similarly, in subjects with moderately low serum testosterone levels, substitution with testosterone does not increase serum 25(OH)D.

  1. Effects of Eurycoma longifolia on Testosterone Level and Bone Structure in an Aged Orchidectomised Rat Model.

    PubMed

    Tajul Ariff, Abdul Shukor; Soelaiman, Ima Nirwana; Pramanik, J; Shuid, Ahmad Nazrun

    2012-01-01

    Testosterone replacement is the choice of treatment in androgen-deficient osteoporosis. However, long-term use of testosterone is potentially carcinogenic. Eurycoma longifolia (EL) has been reported to enhance testosterone level and prevent bone calcium loss but there is a paucity of research regarding its effect on the bone structural parameters. This study was conducted to explore the bone structural changes following EL treatment in normal and androgen-deficient osteoporosis rat model. Thirty-six male Sprague-Dawley rats aged 12 months were divided into normal control, normal rat supplemented with EL, sham-operated, orchidectomised-control, orchidectomised with testosterone replacement, and orchidectomised with EL supplementation groups. Testosterone serum was measured both before and after the completion of the treatment. After 6 weeks of the treatment, the femora were processed for bone histomorphometry. Testosterone replacement was able to raise the testosterone level and restore the bone volume of orchidectomised rats. EL supplementation failed to emulate both these testosterone actions. The inability of EL to do so may be related to the absence of testes in the androgen deficient osteoporosis model for EL to stimulate testosterone production.

  2. Effects of Eurycoma longifolia on Testosterone Level and Bone Structure in an Aged Orchidectomised Rat Model

    PubMed Central

    Tajul Ariff, Abdul Shukor; Soelaiman, Ima Nirwana; Pramanik, J.; Shuid, Ahmad Nazrun

    2012-01-01

    Testosterone replacement is the choice of treatment in androgen-deficient osteoporosis. However, long-term use of testosterone is potentially carcinogenic. Eurycoma longifolia (EL) has been reported to enhance testosterone level and prevent bone calcium loss but there is a paucity of research regarding its effect on the bone structural parameters. This study was conducted to explore the bone structural changes following EL treatment in normal and androgen-deficient osteoporosis rat model. Thirty-six male Sprague-Dawley rats aged 12 months were divided into normal control, normal rat supplemented with EL, sham-operated, orchidectomised-control, orchidectomised with testosterone replacement, and orchidectomised with EL supplementation groups. Testosterone serum was measured both before and after the completion of the treatment. After 6 weeks of the treatment, the femora were processed for bone histomorphometry. Testosterone replacement was able to raise the testosterone level and restore the bone volume of orchidectomised rats. EL supplementation failed to emulate both these testosterone actions. The inability of EL to do so may be related to the absence of testes in the androgen deficient osteoporosis model for EL to stimulate testosterone production. PMID:22966245

  3. Testosterone levels in healthy men and the relation to behavioural and physical characteristics: facts and constructs.

    PubMed

    Zitzmann, M; Nieschlag, E

    2001-03-01

    This review summarises the correlations between testosterone levels and male physical appearance and behaviour. Methodological shortcomings concerning the measurement of testosterone could limit the value of these findings. In addition, testosterone measured in body fluids represents only one step in the cascade of action from production to biological effect, and could therefore provide only a limited view of the complexity of physiological events. Testosterone levels are influenced by conditions that are partly controlled or initiated by the hormone itself, but also by circumstances beyond hormonal or individual control. Different kinds of behaviour are not only subject to influence by environment, but also androgens can reinforce the particular kind of conduct and the behavioural impact can wield negative or positive feedback on testosterone secretion. Therefore, both generalisation and individualisation of study results will lead to doubtful conclusions and prejudices. Results of such studies must be viewed with caution, and over-simplification as well as over-interpretation should be avoided.

  4. Dietary Adjuncts for Improving Testosterone Levels in Hypogonadal Males.

    PubMed

    Kovac, Jason R; Pan, Michael; Arent, Shawn; Lipshultz, Larry I

    2016-11-01

    An increasing number of men are being diagnosed with hypogonadism. While many benefit from testosterone supplementation therapy, others who do not meet the criteria for hormone supplementation have turned to dietary adjuncts as a way or gaining improvements in libido, energy, and physical performance. These oral adjunct medications include controlled substances such as androstenedione, androstenediol as well as other "over-the-counter" options like DHEA (dehydroepiandrosterone) and herbal remedies like Tribulus terrestris This review will focus on the use of these adjunct medications in isolation, or in combination with testosterone supplementation therapy as well as the biochemical nature of the supplements, the results of scientific trials as well as the side effects that limit their use. At the end of this review, physicians will have an improved understanding of the popular testosterone adjuncts being used currently as well as the availability of these substances and how they are used.

  5. Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae).

    PubMed

    Luis, Juana; Ramírez, Lorena; Carmona, Agustín; Ortiz, Guadalupe; Delgado, Jesús; Cárdenas, René

    2009-01-01

    Paternal behavior and testosterone plasma levels in the Volcano Mouse Neotomodon alstoni (Rodentia: Muridae). Although initially it was thought that testosterone inhibited the display of paternal behavior in males of rodents, it has been shown that in some species high testosterone levels are needed for exhibition of paternal care. In captivity, males of Volcano Mouse (Neotomodon alstoni) provide pups the same care provided by the mother, with the exception of suckling. Here we measured plasmatic testosterone concentrations 10 days after mating, five and 20 days postpartum, and 10 days after males were isolated from their families in order to determine possible changes in this hormone, associated to the presence and age of pups. Males of Volcano Mouse exhibited paternal behavior when their testosterone levels were relatively high. Although levels of this hormone did not change with the presence or pups age, males that invested more time in huddling showed higher testosterone levels. It is possible that in the Volcano Mouse testosterone modulates paternal behavior indirectly, as in the California mouse.

  6. Prediction of Long-term Post-operative Testosterone Replacement Requirement Based on the Pre-operative Tumor Volume and Testosterone Level in Pituitary Macroadenoma.

    PubMed

    Lee, Cheng-Chi; Chen, Chung-Ming; Lee, Shih-Tseng; Wei, Kuo-Chen; Pai, Ping-Ching; Toh, Cheng-Hong; Chuang, Chi-Cheng

    2015-11-05

    Non-functioning pituitary macroadenomas (NFPAs) are the most prevalent pituitary macroadenomas. One common symptom of NFPA is hypogonadism, which may require long-term hormone replacement. This study was designed to clarify the association between the pre-operative tumor volume, pre-operative testosterone level, intraoperative resection status and the need of long-term post-operative testosterone replacement. Between 2004 and 2012, 45 male patients with NFPAs were enrolled in this prospective study. All patients underwent transsphenoidal surgery. Hypogonadism was defined as total serum testosterone levels of <2.4 ng/mL. The tumor volume was calculated based on the pre- and post-operative magnetic resonance images. We prescribed testosterone to patients with defined hypogonadism or clinical symptoms of hypogonadism. Hormone replacement for longer than 1 year was considered as long-term therapy. The need for long-term post-operative testosterone replacement was significantly associated with larger pre-operative tumor volume (p = 0.0067), and lower pre-operative testosterone level (p = 0.0101). There was no significant difference between the gross total tumor resection and subtotal resection groups (p = 0.1059). The pre-operative tumor volume and testosterone level impact post-operative hypogonadism. By measuring the tumor volume and the testosterone level and by performing adequate tumor resection, surgeons will be able to predict post-operative hypogonadism and the need for long-term hormone replacement.

  7. Testosterone replacement therapy for older men

    PubMed Central

    Borst, Stephen E; Mulligan, Thomas

    2007-01-01

    Despite intensive research on testosterone therapy for older men, important questions remain unanswered. The evidence clearly indicates that many older men display a partial androgen deficiency. In older men, low circulating testosterone is correlated with low muscle strength, with high adiposity, with insulin resistance and with poor cognitive performance. Testosterone replacement in older men has produced benefits, but not consistently so. The inconsistency may arise from differences in the dose and duration of testosterone treatment, as well as selection of the target population. Generally, studies reporting anabolic responses to testosterone have employed higher doses of testosterone for longer treatment periods and have targeted older men whose baseline circulating bioavailable testosterone levels were low. Most studies of testosterone replacement have reported anabolic that are modest compared to what can be achieved with resistance exercise training. However, several strategies currently under evaluation have the potential to produce greater anabolic effects and to do so in a safe manner. At this time, testosterone therapy can not be recommended for the general population of older men. Older men who are hypogonadal are at greater risk for the catabolic effects associated with a number of acute and chronic medical conditions. Future research is likely to reveal benefits of testosterone therapy for some of these special populations. Testosterone therapy produces a number of adverse effects, including worsening of sleep apnea, gynecomastia, polycythemia and elevation of PSA. Efficacy and adverse effects should be assessed frequently throughout the course of therapy. PMID:18225456

  8. Basal serum testosterone levels correlate with ovarian reserve and ovarian response in cycling women undergoing in vitro fertilization.

    PubMed

    Xiao, Shan; Li, Yubin; Long, Lingli; Luo, Canqiao; Mai, Qingyun

    2016-01-01

    This study aimed to investigate the association between basal serum testosterone levels and in vitro fertilization (IVF) parameters in cycling women. A retrospective cohort study was performed at a clinical IVF center, and 495 women with regular menstruation were enrolled. Serum testosterone levels were measured before the start of IVF treatment cycle. We found that basal serum testosterone levels were negatively associated with female age and FSH/LH ratios. In contrast, we found a positive correlation between serum testosterone levels and the number of oocytes and available embryos. However, there was no significant association between testosterone levels and pregnancy outcome. Our results suggest that basal serum testosterone levels were significantly related to certain classic indicators of ovarian reserve, such as age and FSH/LH ratios. Increased testosterone levels improved ovarian response in cycling women, but they fail to predict pregnancy and miscarriage rate.

  9. Total Testosterone Levels and the Effect of Sildenafil on Type 2 Diabetics with Erectile Dysfunction

    PubMed Central

    Hadeed, Nabeel Najib Fadhil; Thanoon, Imad Abdul-Jabar; Al-Mukhtar, Samir Burhanaldin

    2014-01-01

    Objectives Hypotestosteronemia has been reported in approximately half of type 2 diabetic men in general. This study aims to assess serum total testosterone levels in type 2 diabetics with erectile dysfunction and to correlate the degree of improvement between sildenafil citrate and testosterone levels. Methods A cross sectional and prospective comparative interventional study was conducted at the Diabetic Clinic of Assalam Teaching Hospital in Mosul, during the period from January 1, 2009 through to December 31, 2011. The study enrolled 120 type 2 diabetic males with erectile dysfunction who were analyzed with regard to age, duration of diabetes, duration and severity of erectile dysfunction, serum total testosteron levels and the degree of response to sildenafil citrate in terms of testosterone levels. The data were statistically analyzed using the independent two-sample Student t test, χ2 test and Pearson correlation test. A p-value of <0.05 was considered statistically significant. Results Thirty six percent of type 2 diabetic males with erectile dysfunction were found to have low serum testosterone levels. The hypotestosteronemic and normotestosteronemic subgroups were not significantly different in terms of mean age, duration of diabetes, reduction of libido, and reduction in erectile function. The rate and the degree of improvement of erection by sildenafil in the normo-and-hypotestosteronemic respondents were not significantly different, but the degree of improvement by sildenafil was significantly correlated to testosterone levels among the hypotestosteronemic group. Conclusion Hypotestosteronemia was found in 36% of type 2 diabetic males with erectile dysfunction. The degree of improvement of erectile dysfunction by sildenafil was directly proportional to the serum testosterone levels among the hypotestosteronemic group. Therapeutic supplement with testosterone preparation in the hypotestosteronemic diabetics with erectile dysfunction may improve their

  10. Influence of Altered Mass Loading on Testosterone Levels and Testicular Mass

    NASA Technical Reports Server (NTRS)

    Wang, Tommy J.; Ortiz, R. M.; Wade, C. E.; Hargens, Alan R. (Technical Monitor)

    1996-01-01

    Effects of altered load on testosterone levels and testicular mass in mammals are not well defined. Two separate studies (loading;centrifuged; +2G(sub z) and unloading;hindlimb suspension;HLS) were conducted to provide a better understanding of the effects of mass loading on testosterone levels and testicular mass. Daily urine samples were collected, and testicular mass measured at the end of the study. +2G(sub z): Sprague-Dawley rats (230-250 g) were centrifuged for 12 days at +2G(sub z): 8 centrifuged (EC) and 8 off centrifuge controls (OCC). EC had lower body mass, however relative testicular mass was greater. EC exhibited an increase in excreted testosterone levels between days 2 (T2) and 6 (T6), and returned to baseline at T9. HLS: To assess the effects of unloading Sprague-Dawley rats (125-150 g) were studied for 12 days: 10 suspended (Exp) and 10 ambulatory (Ctl). Exp had lower body mass during the study, with reduced absolute and relative testicular mass. Exp demonstrated lower excreted testosterone levels from T5-T12. Conclusions: Loading appears to stimulate anabolism, as opposed to unloading, as indicated by greater relative testicular mass and excreted testosterone levels. Reported changes in muscle mass during loading and unloading coincide with similar changes in excreted testosterone levels.

  11. High levels of testosterone inhibit ovarian follicle development by repressing the FSH signaling pathway.

    PubMed

    Liu, Tao; Cui, Yu-qian; Zhao, Han; Liu, Hong-bin; Zhao, Shi-dou; Gao, Yuan; Mu, Xiao-li; Gao, Fei; Chen, Zi-jiang

    2015-10-01

    The effect of high concentrations of testosterone on ovarian follicle development was investigated. Primary follicles and granulosa cells were cultured in vitro in media supplemented with a testosterone concentration gradient. The combined effects of testosterone and follicle-stimulating hormone (FSH) on follicular growth and granulosa cell gonadotropin receptor mRNA expression were also investigated. Follicle growth in the presence of high testosterone concentrations was promoted at early stages (days 1-7), but inhibited at later stage (days 7-14) of in vitro culture. Interestingly, testosterone-induced follicle development arrest was rescued by treatment with high concentrations of FSH (400 mIU/mL). In addition, in cultured granulosa cells, high testosterone concentrations induced cell proliferation, and increased the mRNA expression level of FSH receptor (FSHR), and luteinized hormone/choriogonadotropin receptor. It was concluded that high concentrations of testosterone inhibited follicle development, most likely through regulation of the FSH signaling pathway, although independently from FSHR downregulation. These findings are an important step in further understanding the pathogenesis of polycystic ovary syndrome.

  12. Social factors increase fecal testosterone levels in wild male gray-cheeked mangabeys (Lophocebus albigena).

    PubMed

    Arlet, Małgorzata E; Kaasik, Ants; Molleman, Freerk; Isbell, Lynne; Carey, James R; Mänd, Raivo

    2011-04-01

    Testosterone can be expected to play a significant role in mediating behavior and life history in social animals, but the number of species with data from the wild is still too small to make generalizations. We investigated the influence of social factors (social status, aggression, and reproductive females) and environmental variation (rainfall and temperature) on fecal testosterone concentrations in wild male gray-cheeked mangabeys (Lophocebus albigena) living in five groups in Kibale National Park, Uganda. This species is phylogenetically closely related to baboons, but is arboreal, with multi-male, multi-female groups rarely exceeding 20 individuals. We analyzed 358 fecal samples from 21 adult males. We found that the highest-ranking males had the highest testosterone concentrations while immigrant males had the lowest testosterone concentrations. Aggression was not correlated with testosterone levels. The presence of females with sexual swellings at their most tumescent stage increased testosterone concentrations in all males. Finally, individuals tended to have lower testosterone when the temperature was higher.

  13. Do Sex Offenders Have Higher Levels of Testosterone? Results From a Meta-Analysis.

    PubMed

    Wong, Jennifer S; Gravel, Jason

    2016-03-21

    The purpose of the current study is to review the available scientific evidence on the relationship between testosterone and sexual aggression. A systematic search for all primary studies comparing basal testosterone levels in sex offenders and non-sex offenders was undertaken across 20 electronic databases using an explicit search strategy and inclusion/exclusion criteria. A total of seven studies were identified and 11 effect sizes were computed; effects were pooled using both fixed and random effects meta-analysis models. Although individual study findings present a mix of results wherein sex offenders have higher or lower baseline levels of testosterone than non-sex offenders, pooled results indicate no overall difference between groups. Moderators of the analyses suggest possibly lower rates of testosterone in child molesters than controls; however, results are dependent on study weighting. Limitations, policy implications with respect to chemical castration laws, and future directions for research are discussed.

  14. Relationships of Polychlorinated Biphenyls and Dichlorodiphenyldichloroethylene (p,p’-DDE) with Testosterone Levels in Adolescent Males

    PubMed Central

    Gallo, Mia V.; Deane, Glenn D.; Nelder, Kyrie R.; DeCaprio, Anthony P.; Jacobs, Agnes

    2013-01-01

    Background: Concern persists over endocrine-disrupting effects of persistent organic pollutants (POPs) on human growth and sexual maturation. Potential effects of toxicant exposures on testosterone levels during puberty are not well characterized. Objectives: In this study we evaluated the relationship between toxicants [polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p´-DDE), hexachlorobenzene (HCB), and lead] and testosterone levels among 127 Akwesasne Mohawk males 10 to < 17 years of age with documented toxicant exposures. Methods: Data were collected between February 1996 and January 2000. Fasting blood specimens were collected before breakfast by trained Akwesasne Mohawk staff. Multivariable regression models were used to estimates associations between toxicants and serum testosterone, adjusted for other toxicants, Tanner stage, and potential confounders. Results: The sum of 16 PCB congeners (Σ16PCBs) that were detected in ≥ 50% of the population was significantly and negatively associated with serum testosterone levels, such that a 10% change in exposure was associated with a 5.6% decrease in testosterone (95% CI: –10.8, –0.5%). Of the 16 congeners, the more persistent ones (Σ8PerPCBs) were related to testosterone, whereas the less persistent ones, possibly reflecting more recent exposure, were not. When PCB congeners were subgrouped, the association was significant for the sum of eight more persistent PCBs (5.7% decrease; 95% CI: –11, –0.4%), and stronger than the sum of six less persistent congeners (3.1% decrease; 95% CI: –7.2, 0.9%). p,p´-DDE was positively but not significantly associated with serum testosterone (5.2% increase with a 10% increase in exposure; 95% CI: –0.5, 10.9%). Neither lead nor HCB was significantly associated with testosterone levels. Conclusions: Exposure to PCBs, particularly the more highly persistent congeners, may negatively influence testosterone levels among adolescent males. The

  15. Serum testosterone levels and excessive erythrocytosis during the process of adaptation to high altitudes

    PubMed Central

    Gonzales, Gustavo F

    2013-01-01

    Populations living at high altitudes (HAs), particularly in the Peruvian Andes, are characterized by a mixture of subjects with erythrocytosis (16 g dl−121 g dl−1). Elevated haemoglobin values (EE) are associated with chronic mountain sickness, a condition reflecting the lack of adaptation to HA. According to current data, native men from regions of HA are not adequately adapted to live at such altitudes if they have elevated serum testosterone levels. This seems to be due to an increased conversion of dehydroepiandrosterone sulphate (DHEAS) to testosterone. Men with erythrocytosis at HAs show higher serum androstenedione levels and a lower testosterone/androstenedione ratio than men with EE, suggesting reduced 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activity. Lower 17beta-HSD activity via Δ4-steroid production in men with erythrocytosis at HA may protect against elevated serum testosterone levels, thus preventing EE. The higher conversion of DHEAS to testosterone in subjects with EE indicates increased 17beta-HSD activity via the Δ5-pathway. Currently, there are various situations in which people live (human biodiversity) with low or high haemoglobin levels at HA. Antiquity could be an important adaptation component for life at HA, and testosterone seems to participate in this process. PMID:23524530

  16. A herbal medicine, saikokaryukotsuboreito, improves serum testosterone levels and affects sexual behavior in old male mice.

    PubMed

    Zang, Zhi Jun; Ji, Su Yun; Dong, Wang; Zhang, Ya Nan; Zhang, Er Hong; Bin, Zhang

    2015-06-01

    Late-onset hypogonadism (LOH) is a clinical syndrome characterized with aging and declined serum testosterone levels. Sexual symptoms are also essential for the diagnosis of LOH. Testosterone replacement therapy is used widely to treat LOH. However, the side effects of it should not be ignored, such as fluid retention, hypertension and spermatogenic suppression. Therefore, alternate treatment modalities have been pursued. Herbal medicines used widely in China have achieved satisfying results with little side effects. Nonetheless, there are few pharmacological researches on them. In this study, 24-month-old mice were used as LOH animal models to explore the pharmacological effects of a herbal medicine, saikokaryukotsuboreito (SKRBT), on serum testosterone levels and sexual functions. Furthermore, the expression of steroidogenic acute regulatory (StAR) protein, a kind of rate-limiting enzyme of testosterone synthesis, was also examined. As a result, SKRBT improved the serum testosterone levels of these mice at a dose of 300 and 450 mg/kg. Multiple measures of sexual behavior were enhanced. The expression of StAR was also increased. Therefore, this study suggested that SKRBT can improve the serum testosterone levels by activating the expression of StAR and might be a viable option to treat sexual symptoms caused by LOH.

  17. Fathers have lower salivary testosterone levels than unmarried men and married non-fathers in Beijing, China

    PubMed Central

    Gray, Peter B; Jeffrey Yang, Chi-Fu; Pope, Harrison G

    2005-01-01

    A growing body of evidence, almost entirely from North America, has found that male testosterone levels are positively associated with mating effort (male–male competition and mate-seeking behaviour), while lower testosterone levels have been associated with affiliative pair bonding and paternal care. To expand the cross-cultural scope of this research, here we investigate variation in salivary testosterone levels among Chinese men in relation to marital and parenting variables. One hundred and twenty-six men drawn from a Beijing university setting between the ages of 21 and 38 completed a questionnaire and provided both morning and late afternoon saliva samples from which testosterone levels were measured. The 66 unmarried men had slightly higher levels of testosterone than the 30 married non-fathers, but this difference was not statistically significant. However, the 30 fathers exhibited significantly lower testosterone levels than both unmarried men and married non-fathers. Among married non-fathers, marital relationship quality was not significantly related to testosterone levels. Among married fathers, men with children aged less than 4 years of age did not have lower testosterone levels than men with older children. These data are the first outside of North America to show lower testosterone levels among fathers, and lend support to the theoretical view that male testosterone levels differ according to mating and parenting effort. PMID:16543176

  18. The putative effects of D-Aspartic acid on blood testosterone levels: A systematic review

    PubMed Central

    Roshanzamir, Farzad; Safavi, Seyyed Morteza

    2017-01-01

    Background: D-Aspartic acid (D-Asp) is in invertebrate and vertebrate neuroendocrine tissues, where it carries out important physiological functions. Recently, it has been reported that D-Asp is involved in the synthesis and release of testosterone and is assumed can be used as a testosterone booster for infertile men, and by athletes to increase muscle mass and strength. Objective: The aim of this review is to summarize available evidence related to the effects of D-Asp on serum testosterone levels. Materials and Methods: We conducted a systematic review of all type studies, which evaluated the effect of the D-Asp on blood testosterone including published papers until October 2015, using PubMed, ISI Web of Science, ProQuest and Scopus database. Results: With 396 retrieved records, 23 animal studies and 4 human studies were included. In vivo and in vitro animal studies revealed the effect of D-Asp depending on species, sex and organ-specific. Our results showed that exogenous D-Asp enhances testosterone levels in male animal’s studies, whereas studies in human yielded inconsistent results. The evidence for this association in man is still sparse, mostly because of limited number and poor quality studies. Conclusion: There is an urgent need for more and well-designed human clinical trials with larger sample sizes and longer duration to investigate putative effects of D-Asp on testosterone concentrations. PMID:28280794

  19. Low testosterone levels and unimpaired melatonin secretion in young males with metabolic syndrome.

    PubMed

    Robeva, R; Kirilov, G; Tomova, A; Kumanov, P

    2006-12-01

    The interrelations between testosterone, insulin and melatonin levels in males with metabolic syndrome (MS) are still not clarified, especially in young age groups. The aim of the present study was to compare the testosterone serum levels in young men with MS to those in healthy controls, and to determine the possible changes in their melatonin rhythm, as well as the relation between melatonin, insulin and lipid profile. Fasting insulin and testosterone concentrations were measured in 10 healthy nonobese and 10 MS patients. Blood samples for melatonin, insulin and luteinizing hormone (LH) were collected at 19.00, 03.00 and 11.00 hours. A significant difference was found between the testosterone levels in controls and patients. Luteinizing hormone levels in both groups were similar, however, higher night LH levels in MS patients were observed. No changes in the melatonin concentrations of the two groups were found. In conclusion, total testosterone levels were significantly lower in young men with MS compared with healthy age-matched controls. Mild hypoandrogenia in hyperinsulinaemic patients was not related with changes in their melatonin levels. No alterations in the endogenous melatonin rhythm of the MS patients were found.

  20. Testosterone Therapies.

    PubMed

    Khera, Mohit

    2016-05-01

    There are numerous testosterone formulations now available, and patients and clinicians should take into account the "4 Cs": cost, compliance, convenience, and concentration levels. Testosterone is a natural contraceptive and should not be used in men trying to achieve a pregnancy. All testosterone gels and solutions have an increased risk of transference, and there should be increased caution when in contact with children and pregnant women.

  1. Circulating testosterone and inhibin levels at different ages in the male beluga (Delphinapterus leucas).

    PubMed

    Katsumata, Etsuko; Ueda, Yoko; Arai, Kazutoshi; Katsumata, Hiroshi; Kishimoto, Miori; Watanabe, Gen; Taya, Kazuyoshi

    2012-03-01

    This study is the first report on circulating testosterone and inhibin levels in a species of whales, the beluga. Circulating testosterone and immunoreactive (ir-) inhibin levels in two captive male belugas ("Nack", originally from Canada and "Duke", from the Okhotsk Sea) were measured every month for 9 years between 1995 and 2003. Assuming that clearly increased testosterone levels in the circulation indicates that the belugas had reached sexual maturity, at the ages of 10 ("Nack") and 11 years old ("Duke"). Their testosterone levels before the significant increase (pre-pubertal) were 0.42 ± 0.07 ng/ml (n=18) and 0.35 ± 0.10 ng/ml (n=18) and, those of after the increase (maturity) were 1.65 ± 0.14 ng/m l (n=74) and 2.06 ± 0.14 ng/ml (n=74). Circulating ir-inhibin levels before sexual maturity were 0.78 ± 0.04 ng/ml (n=18) and 0.64 ± 0.04 ng/ml (n=15) and, after sexual maturity were 0.52 ± 0.02 ng/ml (n=56) and 0.43 ± 0.02 ng/ml (n=67). Seasonal changes were observed in the testosterone levels after sexual maturity and the levels increased during March and April in Canadian origin "Nack", and peaked in February in Okhotsk origin "Duke". Circulating ir-inhibin level gradually decreased as they aged. A negative correlation between the circulating testosterone and ir-inhibin was observed. No seasonal changes were observed in the ir-inhibin levels after sexual maturity. These data will surely correspond to clarification of endocrinology and the successful reproduction of the beluga.

  2. Comparison of Serum Cortisol and Testosterone Levels in Acute and Chronic Central Serous Chorioretinopathy

    PubMed Central

    Natung, Tanie

    2015-01-01

    Purpose To compare the levels of serum cortisol and testosterone in acute and chronic central serous chorio-retinopathy (CSC). Methods Serum cortisol and testosterone levels in 30 patients with either acute or chronic CSC were evaluated using chemiluminescent immunoassay. Results The mean age was 42.43 ± 6.37 years (range, 32 to 56 years). The mean 8:00 to 9.00 a.m. serum cortisol level was 12.61 ± 4.74 µg/dL (range, 6.58 to 27.42 µg/dL). The mean serum testosterone level was 5.88 ± 1.57 ng/dL (range, 2.81 to 9.94 ng/dL). The mean visual acuity was 20 / 65.07 ± 40.56 (range, 20 / 25 to 20 / 200). There was no statistically significant difference in the mean levels of serum cortisol and testosterone between the acute and chronic cases (p > 0.05), but there was a statistically significant difference in the mean presenting visual acuity in the two groups (p < 0.05). Conclusions All except one patient in the acute group had normal levels of serum cortisol. Testosterone levels were within the normal range in both the acute and chronic cases of CSC. There is unlikely to be any statistically significant difference in the mean levels of serum cortisol and testosterone between the acute and chronic cases, but there may be a statistically significant difference in the mean presenting visual acuity in these groups. PMID:26635454

  3. Are Men’s Perceptions of Sexually Dimorphic Vocal Characteristics Related to Their Testosterone Levels?

    PubMed Central

    Hahn, Amanda C.; Wincenciak, Joanna; Fisher, Claire I.; Pisanski, Katarzyna; Feinberg, David R.; DeBruine, Lisa M.; Jones, Benedict C.

    2016-01-01

    Feminine physical characteristics in women are positively correlated with markers of their mate quality. Previous research on men’s judgments of women’s facial attractiveness suggests that men show stronger preferences for feminine characteristics in women’s faces when their own testosterone levels are relatively high. Such results could reflect stronger preferences for high quality mates when mating motivation is strong and/or following success in male-male competition. Given these findings, the current study investigated whether a similar effect of testosterone occurs for men’s preferences for feminine characteristics in women’s voices. Men’s preferences for feminized versus masculinized versions of women’s and men’s voices were assessed in five weekly test sessions and saliva samples were collected in each test session. Analyses showed no relationship between men’s voice preferences and their testosterone levels. Men’s tendency to perceive masculinized men’s and women’s voices as more dominant was also unrelated to their testosterone levels. Together, the results of the current study suggest that testosterone-linked changes in responses to sexually dimorphic characteristics previously reported for men's perceptions of faces do not occur for men's perceptions of voices. PMID:27875569

  4. Serum testosterone level predicts the effective time of androgen deprivation therapy in metastatic prostate cancer patients.

    PubMed

    Wang, Yue; Dai, Bo; Ye, Ding-Wei

    2017-01-01

    Androgen deprivation therapy (ADT) is the standard of care for patients with metastatic prostate cancer. However, whether serum testosterone levels, using a cut-off point of 50 ng dl-1 , are related to the effective time of ADT in newly diagnosed prostate cancer patients remains controversial. Moreover, recent studies have shown that some patients may benefit from the addition of upfront docetaxel chemotherapy. To date, no studies have been able to distinguish patients who will benefit from the combination of ADT and docetaxel chemotherapy. This study included 206 patients who were diagnosed with metastatic prostate cancer and showed progression to castrate-resistance prostate cancer (CRPC). Serum testosterone levels were measured prospectively after ADT for 1, 3, and 6 months. The endpoint was the time to CRPC. In univariate and multivariate analyses, testosterone levels <50 ng dl-1 were not associated with the effective time of ADT. Receiver operating characteristic and univariate analysis showed that testosterone levels of ≤25 ng dl-1 after the first month of ADT offered the best overall sensitivity and specificity for prediction of a longer time to CRPC (adjusted hazard ratio [HR], 1.46; 95% confidence interval [95% CI], 1.08-1.96; P = 0.013). Our results show that serum testosterone level of 25 ng dl-1 plays a prognostic role in prostate cancer patients receiving ADT. A testosterone value of 25 ng dl-1 after the first month of ADT can distinguish patients who benefit from ADT effectiveness for only a short time. These patients may need to receive ADT and concurrent docetaxel chemotherapy.

  5. Serum testosterone level predicts the effective time of androgen deprivation therapy in metastatic prostate cancer patients

    PubMed Central

    Wang, Yue; Dai, Bo; Ye, Ding-Wei

    2017-01-01

    Androgen deprivation therapy (ADT) is the standard of care for patients with metastatic prostate cancer. However, whether serum testosterone levels, using a cut-off point of 50 ng dl−1, are related to the effective time of ADT in newly diagnosed prostate cancer patients remains controversial. Moreover, recent studies have shown that some patients may benefit from the addition of upfront docetaxel chemotherapy. To date, no studies have been able to distinguish patients who will benefit from the combination of ADT and docetaxel chemotherapy. This study included 206 patients who were diagnosed with metastatic prostate cancer and showed progression to castrate-resistance prostate cancer (CRPC). Serum testosterone levels were measured prospectively after ADT for 1, 3, and 6 months. The endpoint was the time to CRPC. In univariate and multivariate analyses, testosterone levels <50 ng dl−1 were not associated with the effective time of ADT. Receiver operating characteristic and univariate analysis showed that testosterone levels of ≤25 ng dl−1 after the first month of ADT offered the best overall sensitivity and specificity for prediction of a longer time to CRPC (adjusted hazard ratio [HR], 1.46; 95% confidence interval [95% CI], 1.08–1.96; P = 0.013). Our results show that serum testosterone level of 25 ng dl−1 plays a prognostic role in prostate cancer patients receiving ADT. A testosterone value of 25 ng dl−1 after the first month of ADT can distinguish patients who benefit from ADT effectiveness for only a short time. These patients may need to receive ADT and concurrent docetaxel chemotherapy. PMID:26975487

  6. Effect of altered reproductive function and lowered testosterone levels on bone density in male endurance athletes

    PubMed Central

    Bennell, Kim L; Brukner, Peter D; Malcolm, Susan A

    1996-01-01

    The effect of intense physical activity on female reproductive hormones is well recognised1–3 and there is evidence that menstrual disturbances associated with hypo-oestrogenism adversely affect bone density especially at the lumbar spine.4 5 Physical activity can also have a range of effects on male reproductive function depending upon the intensity and duration of the activity and the fitness of the individual.6 In particular, endurance training may be associated with reductions in circulating testosterone levels. Since testosterone has important anabolic roles, alterations in reproductive hormone profiles may have detrimental skeletal consequences similar to those seen in females with menstrual disturbances. The aim of this brief review is to present the limited literature on the relation between bone density and testosterone levels in male endurance athletes. PMID:8889111

  7. Paternal behavior increases testosterone levels in offspring of the California mouse.

    PubMed

    Becker, Elizabeth A; Moore, Brett M; Auger, Catherine; Marler, Catherine A

    2010-08-01

    Paternal care during early development influences pup survivorship in the monogamous and biparental California mouse, Peromyscus californicus. Moreover, paternal pup retrievals impact development of adult offspring aggression and the neuropeptide vasopressin, yet little is known about the underlying mechanisms of these developmental changes. Because testosterone can increase arginine vasopressin and aggression, we hypothesized that paternal pup retrievals increase testosterone levels in prepubertal male P. californicus pups. Male pups were assigned to one of three groups: hormonal baseline, nonretrieval control, or retrieval. On postnatal days 18-21, all pups and the mother were removed from the cage, and the focal male pup was placed either outside of the nest to elicit paternal retrievals (retrieval group) or in the nest to discourage paternal retrievals (nonretrieval group). Testosterone was elevated at 45-min, but not 90-min, post-manipulation in retrieved compared to nonretrieved pups. Moreover, there was a significant positive correlation between pup retrievals and testosterone in the 45-min group. This rapid testosterone rise in response to paternal retrievals may facilitate an increase in aggression and vasopressin in adult offspring. Therefore, this period of development previously viewed as hormonally quiescent may be more active in response to paternal behavior than previously thought.

  8. Microvesicles Correlated with Components of Metabolic Syndrome in Men with Type 2 Diabetes Mellitus and Lowered Testosterone Levels But Were Unaltered by Testosterone Therapy

    PubMed Central

    Velling Magnussen, Line; Nielsen, Morten Hjuler; Nielsen, Tine Bo; Højlund, Kurt; Andersen, Marianne Skovsager; Handberg, Aase

    2017-01-01

    Aims. To investigate how circulating microvesicle phenotypes correlate with insulin sensitivity, body composition, plasma lipids, and hepatic fat accumulation. We hypothesized that changes elicited by testosterone replacement therapy are reflected in levels of microvesicles. Methods. Thirty-nine type 2 diabetic males with lowered testosterone levels were assigned to either testosterone replacement therapy or placebo and evaluated at baseline and after 24 weeks. Microvesicles were analysed by flow cytometry and defined as lactadherin-binding particles within the 0.1–1.0 μm gate. Microvesicles of platelet, monocyte, and endothelial cell origin were identified by cell-specific markers and their expression of CD36 was investigated. Results. Triglycerides correlated positively with all investigated microvesicle phenotypes in this study (p < 0.05), and indicators of hepatic fat accumulation, alanine aminotransferase, and gamma glutamyltransferase correlated with platelet and endothelial microvesicles and CD36-expressing microvesicles from platelets and monocytes (p < 0.05). BMI, waist circumference, and fat percentage correlated with CD36-expressing monocyte microvesicles (p < 0.05), while insulin sensitivity did not correlate with any microvesicle phenotypes. Microvesicle levels were unaffected by testosterone therapy. Conclusions. Metabolic syndrome components and hepatic fat accumulation correlated with microvesicle phenotypes, supporting the involvement of especially CD36 on monocytes in metabolic syndrome pathogenesis. Although testosterone therapy improved body composition measures, microvesicle phenotype levels were unaffected. This trial was registered at ClinicalTrials.gov (NCT01560546). PMID:28168203

  9. Heritability and cross-sex genetic correlations of early-life circulating testosterone levels in a wild mammal.

    PubMed

    Pavitt, Alyson T; Walling, Craig A; Pemberton, Josephine M; Kruuk, Loeske E B

    2014-11-01

    Testosterone is an important hormone that has been shown to have sex-specific links to fitness in numerous species. Although testosterone concentrations vary substantially between individuals in a population, little is known about its heritable genetic basis or between-sex genetic correlations that determine its evolutionary potential. We found circulating neonatal testosterone levels to be both heritable (0.160 ± 0.064 s.e.) and correlated between the sexes (0.942 ± 0.648 s.e.) in wild red deer calves (Cervus elaphus). This may have important evolutionary implications if, as in adults, the sexes have divergent optima for circulating testosterone levels.

  10. Testosterone Injection

    MedlinePlus

    ... and testosterone pellet (Testopel) are forms of testosterone injection used to treat symptoms of low testosterone in ... are low before you begin to use testosterone injection. Testosterone enanthate (Delatestryl) and testosterone pellet (Testopel) are ...

  11. High serum testosterone levels during postpartum period are associated with postpartum depression.

    PubMed

    Aswathi, A; Rajendiren, Soundravally; Nimesh, Archana; Philip, R Ravi; Kattimani, Shivanand; Jayalakshmi, D; Ananthanarayanan, P H; Dhiman, Pooja

    2015-10-01

    In view of the reported cases of mood disorders that occur in mothers following childbirth and believing that sex steroid hormones contribute to mood and behavioral changes, this study has been aimed to explore the role of sex steroid hormones as an etiological factor for postpartum depression (PPD). This study was conducted at JIPMER, Puducherry, India between January 2010 and 2011. 103 women were recruited in the study after childbirth, out of which 62 women who were believed to be suffering from PPD were categorized as cases and the remaining 41 with no mood changes as controls, using Edinburgh Postpartum Depression Scale (EPDS) (cases had EPDS score ≥10 at 24-28h, controls had score <10 at 24-48h postpartum). The hormones estimated in these two groups included estradiol, progesterone and testosterone, and their levels were compared between these two groups. A significantly high testosterone levels were observed in cases with PPD at 24-28h when compared to controls. Estradiol and progesterone levels did not show significant difference between cases and controls. ROC analysis done at 24-28h showed that testosterone levels beyond 42.71ng/mL predict the development of PPD with 79% sensitivity, 63% specificity, 68% positive predictive value, 74% negative predictive value with AUC being 0.708. This study shows that there is an association between persistent high serum testosterone level in women following childbirth and PPD.

  12. Correlation between Male Social Status, Testosterone Levels, and Parasitism in a Dimorphic Polygynous Mammal

    PubMed Central

    Negro, Sandra S.; Caudron, Abigail K.; Dubois, Michel; Delahaut, Philippe; Gemmell, Neil J.

    2010-01-01

    Life history trade-offs have often been assumed to be the consequence of restrictions in the availability of critical resources such as energy and nutrients, which necessitate the differential allocation of resources to costly traits. Here, we examined endocrine (testosterone) and health (parasite burdens) parameters in territorial and non-territorial New Zealand fur seal males. We documented intra-sexual differences in sexual behaviours, testosterone levels, and parasitism that suggest a trade-off exists between reproductive success and physical health, particularly susceptibility to helminths and acanthocephalans, in males displaying different mating tactics (i.e., territorial and non-territorial tactics). Levels of testosterone were higher in territorial males and correlated positively with reproductive effort (i.e., intra- and inter-sexual interactions). However, these territorial males also exhibited high levels of parasitic infection, which may impair survival in the long-term. Our study, while limited in sample size, provides preliminary evidence for a link between male mating tactics, testosterone levels and parasite loads, and potential effects on reproductive success and life history that should be explored further. PMID:20856933

  13. Circularly polarized, sinusoidal, 50 Hz magnetic field exposure does not influence plasma testosterone levels of rats.

    PubMed

    Kato, M; Honma, K; Shigemitsu, T; Shiga, Y

    1994-01-01

    We exposed rats to circularly polarized 50 Hz magnetic fields to determine if plasma testosterone concentration was affected. Previous experiments indicate that magnetic fields suppress the nighttime rise in melatonin, suggesting that other neuroendocrine changes might occur as well. Male Wistar-King rats were exposed almost continuously for 6 weeks to magnetic flux densities of 1, 5, or 50 microT. Blood samples were obtained by decapitation at 12:00 h and 24:00 h. Plasma testosterone concentration showed a significant day-night difference, with a higher level at 12:00 h when studied in July and December, but night difference, with a higher level at 12:00 h when studied in July and December, but the day-night difference disappeared when concentrations were studied in April. In three experiments, magnetic field exposure had no statistically significant effect on plasma testosterone levels compared with the sham-exposed groups. These findings indicate that 6 weeks of nearly continuous exposure to circularly polarized, 50 Hz magnetic fields did not change plasma testosterone concentration in rats.

  14. Prenatal Hyperandrogenization Induces Metabolic and Endocrine Alterations Which Depend on the Levels of Testosterone Exposure

    PubMed Central

    Amalfi, Sabrina; Velez, Leandro Martín; Heber, María Florencia; Vighi, Susana; Ferreira, Silvana Rocío; Orozco, Adriana Vega; Pignataro, Omar; Motta, Alicia Beatriz

    2012-01-01

    Prenatal hyperandrogenism is able to induce polycystic ovary syndrome (PCOS) in rats. The aim of the present study was to establish if the levels of prenatal testosterone may determine the extent of metabolic and endocrine alterations during the adult life. Pregnant Sprague Dawley rats were prenatally injected with either 2 or 5 mg free testosterone (groups T2 and T5 respectively) from day 16 to day 19 day of gestation. Female offspring from T2 and T5 displayed different phenotype of PCOS during adult life. Offspring from T2 showed hyperandrogenism, ovarian cysts and ovulatory cycles whereas those from T5 displayed hyperandrogenism, ovarian cysts and anovulatory cycles. Both group showed increased circulating glucose levels after the intraperitoneal glucose tolerance test (IPGTT; an evaluation of insulin resistance). IPGTT was higher in T5 rats and directly correlated with body weight at prepubertal age. However, the decrease in the body weight at prepubertal age was compensated during adult life. Although both groups showed enhanced ovarian steroidogenesis, it appears that the molecular mechanisms involved were different. The higher dose of testosterone enhanced the expression of both the protein that regulates cholesterol availability (the steroidogenic acute regulatory protein (StAR)) and the protein expression of the transcriptional factor: peroxisome proliferator-activated receptor gamma (PPAR gamma). Prenatal hyperandrogenization induced an anti-oxidant response that prevented a possible pro-oxidant status. The higher dose of testosterone induced a pro-inflammatory state in ovarian tissue mediated by increased levels of prostaglandin E (PG) and the protein expression of cyclooxygenase 2 (COX2, the limiting enzyme of PGs synthesis). In summary, our data show that the levels of testosterone prenatally injected modulate the uterine environment and that this, in turn, would be responsible for the endocrine and metabolic abnormalities and the phenotype of PCOS

  15. Testosterone Therapy in Men

    MedlinePlus

    ... softness of the testicles Size of the penis Measurement of testosterone levels Generally, blood levels of testosterone ... levels may be different in different laboratories. Morning measurement (when levels are highest) is recommended. Illness, malnutrition, ...

  16. Testosterone levels and cognitive functioning in women with polycystic ovary syndrome and in healthy young women.

    PubMed

    Schattmann, Linda; Sherwin, Barbara B

    2007-05-01

    We investigated the possible influence of testosterone (T) on cognitive functioning in women with polycystic ovary syndrome (PCOS), an endocrine disorder associated with elevated levels of free testosterone (free T). Performance on a battery of neuropsychological tests in 29 women with elevated free T levels due to PCOS was compared to the performance of 22 age- and education-matched, healthy control women with free T levels in the normal female range. Women with PCOS had significantly higher levels of free T (estimated by the free androgen index) and demonstrated significantly worse performance on tests of verbal fluency, verbal memory, manual dexterity, and visuospatial working memory than the healthy control women. No differences between the groups were found on tests of mental rotation, spatial visualization, spatial perception, or perceptual speed. These results suggest that, in women, elevations in free T may be associated with poorer performance on cognitive tasks that tend to show a female advantage.

  17. Serum testosterone as a biomarker for second prostatic biopsy in men with negative first biopsy for prostatic cancer and PSA>4ng/mL, or with PIN biopsy result

    PubMed Central

    Fiamegos, Alexandros; Varkarakis, John; Kontraros, Michael; Karagiannis, Andreas; Chrisofos, Michael; Barbalias, Dimitrios; Deliveliotis, Charalampos

    2016-01-01

    Abstract Introduction: Data from animal, clinical and prevention studies support the role of androgens in prostate cancer growth, proliferation and progression. Results of serum based epidemiologic studies in humans, however, have been inconclusive. The present study aims to define whether serum testosterone can be used as a predictor of a positive second biopsy in males considered for re-biopsy. Material and Methods: The study included 320 men who underwent a prostatic biopsy in our department from October 2011 until June 2012. Total testosterone, free testosterone, bioavailable testosterone and prostate pathology were evaluated in all cases. Patients undergoing a second biopsy were identified and biopsy results were statistically analyzed. Results: Forty men (12.5%) were assessed with a second biopsy. The diagnosis of the second biopsy was High Grade Intraepithelial Neoplasia in 14 patients (35%) and Prostate Cancer in 12 patients (30%). The comparison of prostatic volume, total testosterone, sex hormone binding globulin, free testosterone, bioavailable testosterone and albumin showed that patients with cancer of the prostate had significantly greater levels of free testosterone (p=0.043) and bioavailable T (p=0.049). Conclusion: In our study, higher free testosterone and bioavailable testosterone levels were associated with a cancer diagnosis at re-biopsy. Our results indicate a possible role for free and bioavailable testosterone in predicting the presence of prostate cancer in patients considered for re-biopsy. PMID:27532110

  18. Association Between Serum Levels of Testosterone and Estradiol With Meibomian Gland Assessments in Postmenopausal Women

    PubMed Central

    Ablamowicz, Anna F.; Nichols, Jason J.; Nichols, Kelly K.

    2016-01-01

    Purpose The aims of this analysis were to determine if there is an association between serum levels of testosterone and estradiol with meibomian gland (MG) morphology and lipid layer thickness. Methods The data used for this analysis were collected from postmenopausal women with and without dry eye disease. Meibography was used to assess MG dropout on the central two-thirds of the eyelid and biomicroscopy was used for assessing MG expressibility and meibum quality. Venous blood samples were drawn for serum hormone level analysis. The Kruskal-Wallis test and Spearman correlations were used for statistical analysis. Results One hundred ninety-eight postmenopausal women with an average age of 61.2 (±9.1) years were included in this analysis. Testosterone levels showed significant differences between MG dropout grades 1 and 4 (P = 0.002) and grades 2 and 4 (P = 0.01), whereas estradiol levels were different based on MG dropout (P = 0.53). No significant correlations were found between testosterone (r = 0.10, P = 0.17) or estradiol (r = 0.05, P = 0.45) and lipid layer thickness. Conclusions Testosterone levels were increased with MG dropout, which was significant between the mild and severe dropout groups, whereas no significant differences were found with estradiol and any MG assessment. Although the literature suggests an association of serum hormone levels and pathogenesis of dry eye disease in postmenopausal women, analysis of active sex steroid precursors and local tissue hormone levels may prove more useful. PMID:26830366

  19. Moderating effects of salivary testosterone levels on associations between job demand and psychological stress response in Japanese medical workers.

    PubMed

    Hirokawa, Kumi; Miwa, Machiko; Taniguchi, Toshiyo; Tsuchiya, Masao; Kawakami, Norito

    2016-06-10

    Levels of job stress have been shown to be inversely associated with testosterone levels, but some inconsistent results have been documented. We investigated the moderating effects of testosterone levels on associations between job stress-factors and psychological stress responses in Japanese medical workers. The participants were 63 medical staff (20 males and 43 women; mean age: 30.6 years; SD=7.3) in Okayama, Japan. Their job-stress levels and psychological stress responses were evaluated using self-administered questionnaires, and their salivary testosterone collected. Multiple regression analyses showed that job demand was positively associated with stress responses in men and women. An interaction between testosterone and support from colleagues had a significant effect on depression and anxiety for women. In women with lower testosterone levels, a reducing effect of support from colleagues on depression and anxiety was intensified. In women with higher testosterone levels, depression and anxiety levels were identical regardless of support from colleagues. Testosterone may function as a moderator between perceived work environment and psychological stress responses for female medical workers.

  20. Pre-GnRH and GnRH-induced testosterone levels do not vary across behavioral contexts: A role for individual variation.

    PubMed

    Ambardar, Medhavi; Grindstaff, Jennifer L

    2017-05-15

    Hormones can facilitate the expression of behavior, but relatively few studies have considered individual variation and repeatability in hormone-behavior relationships. Repeated measures of hormones are valuable because repeatability in hormone levels might be a mechanism that drives repeatability in behavior ("personality"). Testosterone is predicted to promote territorial aggression and suppress parental behaviors. In our population of eastern bluebirds (Sialia sialis), parental care and nest defense aggression toward a heterospecific are repeatable. We tested the hypothesis that repeatability of testosterone levels within individuals underlies repeatable behaviors observed in our population. We measured nestling provisioning and aggressive nest defense against a heterospecific. After behavioral observations we captured either the male or female bluebird, and determined initial testosterone levels and maximum capacity of the gonads to secrete testosterone by injecting gonadotropin-releasing hormone (GnRH). We found among-individual variation in initial testosterone levels for males and females. Individual males were repeatable in both initial and GnRH-induced testosterone levels across behavioral contexts, while individual females were repeatable in GnRH-induced testosterone levels. However, testosterone levels were not significantly related to parental or nest defense behaviors, suggesting that repeatable testosterone levels may not drive repeatable parental and heterospecific nest defense behaviors in this population. The absence of a relationship between testosterone and parental and heterospecific nest defense behaviors might be due to among-individual variation in testosterone levels. Considering the sources of variation in testosterone levels may reveal why some populations exhibit high individual variation in hormone levels.

  1. Nucleus accumbens response to rewards and testosterone levels are related to alcohol use in adolescents and young adults

    PubMed Central

    Braams, Barbara R.; Peper, Jiska S.; van der Heide, Dianne; Peters, Sabine; Crone, Eveline A.

    2016-01-01

    During adolescence there is a normative increase in risk-taking behavior, which is reflected in, for example, increases in alcohol consumption. Prior research has demonstrated a link between testosterone and alcohol consumption, and between testosterone and neural responses to rewards. Yet, no study to date tested how testosterone levels and neural responses to rewards relate to and predict individual differences in alcohol use. The current study aimed to investigate this by assessing alcohol use, testosterone levels and neural responses to rewards in adolescents (12–17 years old) and young adults (18–26 years old). Participants were measured twice with a two-year interval between testing sessions. Cross-sectional analysis showed that at the second time point higher neural activity to rewards, but not testosterone levels, explained significant variance above age in reported alcohol use. Predictive analyses showed that, higher testosterone level at the first time point, but not neural activity to rewards at the first time point, was predictive of more alcohol use at the second time point. These results suggest that neural responses to rewards are correlated with current alcohol consumption, and that testosterone level is predictive of future alcohol consumption. These results are interpreted in the context of trajectory models of adolescent development. PMID:26771250

  2. Nucleus accumbens response to rewards and testosterone levels are related to alcohol use in adolescents and young adults.

    PubMed

    Braams, Barbara R; Peper, Jiska S; van der Heide, Dianne; Peters, Sabine; Crone, Eveline A

    2016-02-01

    During adolescence there is a normative increase in risk-taking behavior, which is reflected in, for example, increases in alcohol consumption. Prior research has demonstrated a link between testosterone and alcohol consumption, and between testosterone and neural responses to rewards. Yet, no study to date tested how testosterone levels and neural responses to rewards relate to and predict individual differences in alcohol use. The current study aimed to investigate this by assessing alcohol use, testosterone levels and neural responses to rewards in adolescents (12-17 years old) and young adults (18-26 years old). Participants were measured twice with a two-year interval between testing sessions. Cross-sectional analysis showed that at the second time point higher neural activity to rewards, but not testosterone levels, explained significant variance above age in reported alcohol use. Predictive analyses showed that, higher testosterone level at the first time point, but not neural activity to rewards at the first time point, was predictive of more alcohol use at the second time point. These results suggest that neural responses to rewards are correlated with current alcohol consumption, and that testosterone level is predictive of future alcohol consumption. These results are interpreted in the context of trajectory models of adolescent development.

  3. [Effect of the treatment on hemodynamic indicators and plasma testosterone level in patients with juvenile hypertension].

    PubMed

    Zanozdra, N S; Chernoguz, L S; Kupchinskaia, E G; Krishchuk, A A; Savitskiĭ, S Iu; Popova, L I

    1990-07-01

    The effect of anapriline, corinfar and reserpine on parameters of hemodynamics and plasma testosterone was evaluated in 60 juvenile hypertension patients who achieved pronounced hypotensive response. It was established that the level of sex hormones tended to diminution by the end of the treatment month 1 or 2, this drop being more noticeable in reserpine administration. Basing on this evidence it would be beneficial for patients suffering from juvenile hypertension in need of chemotherapy to take courses of the above drugs.

  4. Natesto™ , a novel testosterone nasal gel, normalizes androgen levels in hypogonadal men.

    PubMed

    Rogol, A D; Tkachenko, N; Bryson, N

    2016-01-01

    Advantages of testosterone nasal gel include ease of administration, low dose, and no risk of secondary transference. The efficacy and safety of testosterone nasal gel was evaluated in hypogonadal males. The ninety-day, randomized, open-label, dose-ranging study, included potential dose titration and sequential safety extensions to 1 year. At 39 US outpatient sites, 306 men (mean age 54.4 years) with two fasting morning total serum testosterone levels <300 ng/dL were randomized (n = 228, b.i.d. dosing; n = 78, t.i.d. dosing). Natesto(™) Testosterone Nasal Gel was self-administered, using a multiple-dose dispenser, as two or three daily doses (5.5 mg per nostril, 11.0 mg single dose). Total daily doses were 22 mg or 33 mg. The primary endpoint was the Percentage of patients with Day-90 serum total testosterone average concentration (C(avg)) value within the eugonadal range (≥300 ng/dL, ≤1050 ng/dL). At Day 90, 200/273 subjects (73%; 95% CI 68, 79) in the intent-to-treat (ITT) population and 180/237 subjects (76%; 71, 81) in the per-protocol (PP) population were in the normal range. Also, in the normal range were 68% (61, 74) of ITT subjects and 70% (63, 77) of PP subjects in the titration arm, as well as, 90% (83, 97) of ITT subjects and 91% (84, 98) of PP subjects in the fixed-dose arm. Natesto(™) 11 mg b.i.d. or 11 mg t.i.d. restores normal serum total testosterone levels in most hypogonadal men. Erectile function, mood, body composition, and bone mineral density improved from baseline. Treatment was well tolerated; adverse event rates were low. Adverse event discontinuation rates were 2.1% (b.i.d.) and 3.7% (t.i.d.). This study lacked a placebo or an active comparator control which limited the ability to adequately assess some measures.

  5. Testosterone enhances functional recovery after stroke through promotion of antioxidant defenses, BDNF levels and neurogenesis in male rats.

    PubMed

    Fanaei, Hamed; Karimian, Seyed Morteza; Sadeghipour, Hamid Reza; Hassanzade, Gholamreza; Kasaeian, Amir; Attari, Fatemeh; Khayat, Samira; Ramezani, Vahid; Javadimehr, Mani

    2014-04-16

    It is reported that circulating testosterone levels decrease after cerebral ischemia. The aim of this study was to evaluate the effects of testosterone on oxidative stress, brain-derived neurotrophic factor (BDNF) levels, neurogenesis, histological damage and sensorimotor recovery in a castrated male rat model of focal cerebral ischemia. Animals were divided into four groups. For all animals, castrations were conducted 7 days before transient middle cerebral artery occlusion (MCAO) was done and cerebral ischemia was induced. The first group served as sham. Second was MCAO group and received vehicle only, third was MCAO group that was post-treated with testosterone and the fourth was MCAO group post-treated with testosterone and flutamide. Treatment only with testosterone significantly weakened oxidative stress and increased BDNF levels and sensorimotor recovery during a 10 days period. Rats receiving testosterone demonstrated a significant reduction in infarct volume and a significant increase in neurogenesis on 10th day after focal cerebral ischemia. Our results for the first time showed a potential advantageous effect of testosterone after cerebral ischemia in male rats, which was probably mediated by promoting antioxidant defenses, BDNF levels and neurogenesis.

  6. Changes in Testosterone Levels and Sex Hormone-Binding Globulin Levels in Extremely Obese Men after Bariatric Surgery

    PubMed Central

    Laichuthai, Nitchakarn; Suwannasrisuk, Preaw; Houngngam, Natnicha; Udomsawaengsup, Suthep; Snabboon, Thiti

    2016-01-01

    Objective. Obesity is a risk factor for hypogonadotropic hypogonadism in men. Weight loss has been shown to improve hypogonadism in obese men. This study evaluated the early changes in sex hormones profile after bariatric surgery. Methods. This is a prospective study including 29 morbidly obese men. Main outcomes were changes in serum levels of total testosterone (TT), free testosterone (cFT), SHBG, estradiol, adiponectin, and leptin at 1 and 6 months after surgery. Results. The mean age of patients was 31 ± 8 years and the mean BMI was 56.8 ± 11.7 kg/m2. Fifteen patients underwent Roux-en-Y gastric bypass and 14 patients underwent sleeve gastrectomy. At baseline, 22 patients (75.9%) had either low TT levels (<10.4 nmol/L) or low cFT levels (<225 pmol/L). Total testosterone and SHBG levels increased significantly at 1 month after surgery (p ≤ 0.001). At 6 months after surgery, TT and cFT increased significantly (p ≤ 0.001) and 22 patients (75.9%) had normalized TT and cFT levels. There were no changes in estradiol levels at either 1 month or 6 months after surgery. Conclusions. Increases in TT and SHBG levels occurred early at 1 month after bariatric surgery while improvements in cFT levels were observed at 6 months after bariatric surgery. PMID:27725831

  7. Postnatal testosterone levels and disorder relevant behavior in the second year of life.

    PubMed

    Saenz, Janet; Alexander, Gerianne M

    2013-09-01

    The objective of the current study was to investigate the relationship between testosterone collected at 3-4 months of age and sex-linked disorder-relevant behaviors in the second year of life. Eighty-four children participated at 3-4 (when salivary testosterone levels were obtained and second to fourth digit ratios were measured) and 18-24 months of age (when behavioral ratings of aggression and verbal ability were coded from two 8-min play sessions). Parents also completed the Brief Infant-Toddler Social and Emotional Assessment, and the four subscales (Internalizing, Externalizing, Dysregulation, and Autism Spectrum Disorder) were used to indicate child specific problems. Greater postnatal testosterone levels in early infancy were predictive of more male-typical behaviors in the second year of life (i.e., more autism spectrum behaviors, less time vocalizing, and more Internalizing Problems). These results support the hypothesis that early infancy may be another critical period for the development of gender-linked behavior.

  8. Parental care, loss of paternity and circulating levels of testosterone and corticosterone in a socially monogamous song bird

    PubMed Central

    2014-01-01

    Introduction In biparental birds testosterone levels of males are typically high during the mating phase and decrease during the parental phase. Testosterone implants may enhance mating behaviors, increase the likelihood of males to engage in extra-pair mating behavior and may reduce paternal care. Thus, sex steroids such as testosterone influence reproductive behaviors. Little is known, however, as to whether the more subtle differences in physiological concentrations of testosterone that occur between individuals are related to differences in paternal care, extra-pair behavior, and genetic paternity between those males. Here, we investigate these relationships in the male black redstart (Phoenicurus ochruros), a socially monogamous songbird with a low breeding synchrony. We used nestling provisioning as a proxy for parental care behavior and genetic paternity loss as a proxy for the efficiency of mate-guarding. Results There was no relationship between nestling provisioning and paternity loss of males. Baseline and gonadotropin releasing hormone (GnRH)-induced levels of testosterone, but not baseline corticosterone, were significantly higher during the mating than during the provisioning phase. Males fed more often when temperatures decreased and fed less when they sang more, but we found no correlation between parental behavior and baseline or GnRH-induced testosterone, and baseline corticosterone – both measured during either the mating or the parental phase. However, males that experienced loss of paternity had lower levels of testosterone during the provisioning phase than males that did not lose paternity. Further, males that lost paternity also expressed higher baseline levels of corticosterone. Conclusions Physiological differences in testosterone or baseline corticosterone were not related to differences in parental care, suggesting that the variation of testosterone within a physiological range may not relate to the degree of paternal care in this

  9. The curvelinear correlations between the total testosterone levels and fluid intelligence in men and women.

    PubMed

    Tan, U; Tan, M

    1998-05-01

    The relationship between serum total testosterone (T) level and the fluid intelligence (Cattell's Culture Fair Intelligence Test) was studied in men and women. There was no significant difference between IQs of men and women. There was an inverse curvelinear relationship between IQ and T in women. The same was found also in men, but the declining part of the regression line at high T levels was not as pronounced as in women. It is concluded that T may be related to IQ, even in subjects exhibiting no sex difference in IQ tests; too low or too high T levels may be disadvantages for the fluid intelligence, especially in women.

  10. Salivary Testosterone Levels Under Psychological Stress and Its Relationship with Rumination and Five Personality Traits in Medical Students

    PubMed Central

    Afrisham, Reza; Sadegh-Nejadi, Sahar; SoliemaniFar, Omid; Kooti, Wesam; Ashtary-Larky, Damoon; Alamiri, Fatima; Najjar-Asl, Sedigheh; Khaneh-Keshi, Ali

    2016-01-01

    Objective The purpose of this study was to evaluate the salivary testosterone levels under psychological stress and its relationship with rumination and five personality traits in medical students. Methods A total of 58 medical students, who wanted to participate in the final exam, were selected by simple random sampling. Two months before the exam, in the basal conditions, the NEO Inventory short form, and the Emotional Control Questionnaire (ECQ) were completed. Saliva samples were taken from students in both the basal conditions and under exam stress. Salivary testosterone was measured by ELISA. Data was analyzed using multivariate analysis of variance with repeated measures, paired samples t-test, Pearson correlation and stepwise regression analysis. Results Salivary testosterone level of men showed a significant increase under exam stress (p<0.05). However, a non-significant although substantial reduction observed in women. A significant correlation was found between extroversion (r=-0.33) and openness to experience (r=0.30) with salivary testosterone (p<0.05). Extraversion, aggression control and emotional inhibition predicted 28% of variance of salivary testosterone under stress. Conclusion Salivary testosterone reactivity to stress can be determined by sexual differences, personality traits, and emotional control variables which may decrease or increase stress effects on biological responses, especially the salivary testosterone. PMID:27909455

  11. Prostate size correlates with fasting blood glucose in non-diabetic benign prostatic hyperplasia patients with normal testosterone levels.

    PubMed

    Kim, Won Tae; Yun, Seok Joong; Choi, Young Deuk; Kim, Gi-Young; Moon, Sung-Kwon; Choi, Yung Hyun; Kim, Isaac Yi; Kim, Wun-Jae

    2011-09-01

    We evaluated the correlations between BMI, fasting glucose, insulin, testosterone level, insulin resistance, and prostate size in non-diabetic benign prostatic hyperplasia (BPH) patients with normal testosterone levels. Data from 212 non-diabetic BPH patients with normal testosterone levels, who underwent transurethral resection of the prostate (TURP) due to medical treatment failure, were evaluated retrospectively. Patients with prostate specific antigen (PSA) levels of ≥ 3 ng/mL underwent multicore transrectal prostate biopsy before TURP to rule out prostate cancer. Patients with diabetes mellitus (DM) or serum testosterone levels of < 3.50 ng/mL were excluded from analysis. Correlations between clinical and laboratory parameters were determined. Prostate size correlated positively with age (r = 0.227, P < 0.001), PSA (r = 0.510, P < 0.001), and fasting glucose level (r = 0.186, P = 0.007), but not with BMI, testosterone, insulin level, or insulin resistance (each P > 0.05). Testosterone level inversely correlated with BMI (r = -0.327, P < 0.001), insulin level (r = -0.207, P = 0.003), and insulin resistance (r = -0.221, P = 0.001), but not with age, prostate size, PSA, or fasting glucose level (each P > 0.05). Upon multiple adjusted linear regression analysis, prostate size correlated with elevated PSA (P < 0.001) and increased fasting glucose levels (P = 0.023). In non-DM BPH patients with normal testosterone levels, fasting glucose level is an independent risk factor for prostate hyperplasia.

  12. Decrease in plasma high-density lipoprotein cholesterol levels at puberty in boys with delayed adolescence: correlation with plasma testosterone levels

    SciTech Connect

    Kirkland, R.T.; Keenan, B.S.; Probstfield, J.L.; Patsch, W.; Lin, T.L.; Clayton, G.W.; Insull, W. Jr.

    1987-01-23

    A three-phase study tested the hypothesis that the decrease in the high-density lipoprotein cholesterol (HDL-C) level observed in boys at puberty is related to an increase in the plasma testosterone concentration. In phase I, 57 boys aged 10 to 17 years were categorized into four pubertal stages based on clinical parameters and plasma testosterone levels. These four groups showed increasing plasma testosterone values and decreasing HDL-C levels. In phase II, 14 boys with delayed adolescence were treated with testosterone enanthate. Plasma testosterone levels during therapy were in the adult male range. Levels of HDL-C decreased by a mean of 7.4 mg/dL (0.20 mmol/L) and 13.7 mg/dL (0.35 mmol/L), respectively, after the first two doses. In phase III, 13 boys with delayed adolescence demonstrated increasing plasma testosterone levels and decreasing HDL-C levels during spontaneous puberty. Levels of HDL-C and apolipoprotein A-1 were correlated during induced and spontaneous puberty. Testosterone should be considered a significant determinant of plasma HDL-C levels during pubertal development.

  13. Levels of estradiol and testosterone are altered in Chinese men with sexual dysfunction.

    PubMed

    Wu, F; Chen, T; Mao, S; Jiang, H; Ding, Q; Xu, G

    2016-09-01

    An estimated 20-30% of adult men have at least one manifestation of sexual dysfunction, the most common of which are premature ejaculation (PE) and erectile dysfunction (ED). Emerging evidence has suggested an association between the regulation of hormones with the processes of erection and ejaculation. In this study, we aim to investigate the relationship between sexual dysfunction, namely, PE and ED, and the levels and ratios of estradiol to testosterone in Chinese men. A retrospective case-control study was performed involving 878 male patients aged from 18 to 74 years (mean: 36 years). The ratio of estradiol to testosterone was significantly higher for subjects with ED (7.45 ± 3.09 × 10(-3) ; p < 0.001), and combined PE and ED (6.66 ± 3.05 × 10(-3) ; p = 0.032) compared with that of the control group (6.01 ± 2.61 × 10(-3) ). The ratio was also significantly higher for ED patients when compared with PE patients (5.26 ± 2.18 × 10(-3) ; p < 0.001). Furthermore, compared with the control group, subjects with PE had similar levels of estradiol (95.47 ± 37.86 pmol/L vs. 94.12 ± 32.32 pmol/L; p = 0.678) but significantly higher levels of testosterone (18.66 ± 6.03 nmol/L vs. 16.82 ± 4.93 nmol/L; p < 0.001). This contrasted with the ED group, which showed similar levels of testosterone (16.96 ± 5.86 nmol/L vs. 16.82 ± 4.93 nmol/L; p = 0.773) and significantly higher levels of estradiol (116.88 ± 40.81 pmol/L vs. 94.12 ± 32.32 pmol/L; p < 0.001) compared with control. Subjects with combined ED and PE also had a significantly higher level of estradiol (104.98 ± 43.99 pmol/L vs. 94.12 ± 32.32 pmol/L; p = 0.014) and similar levels of testosterone (17.30 ± 7.23 nmol/L vs. 16.82 ± 4.93 nmol/L; p = 0.503) compared with control. In conclusion, this study involving Chinese males with sexual dysfunction reports, for the first time, that there is an association between sexual dysfunction

  14. Testosterone and Aggression.

    ERIC Educational Resources Information Center

    Archer, John

    1994-01-01

    Studies comparing aggressive and nonaggressive prisoners show higher testosterone levels among the former. While there is limited evidence for a strong association between aggressiveness and testosterone during adolescence, other studies indicate that testosterone levels are responsive to influences from the social environment, particularly those…

  15. Assays of Serum Testosterone.

    PubMed

    Herati, Amin S; Cengiz, Cenk; Lamb, Dolores J

    2016-05-01

    The diagnosis of male hypogonadism depends on an assessment of the clinical signs and symptoms of hypogonadism and serum testosterone level. Current clinical laboratory testosterone assay platforms include immunoassays and mass spectrometry. Despite significant advances to improve the accuracy and precision of the currently available assays, limited comparability exists between assays at the lower and upper extremes of the testosterone range. Because of this lack of comparability, there is no current gold standard assay for the assessment of total testosterone levels.

  16. Low Testosterone Level and Risk of Alzheimer's Disease in the Elderly Men: a Systematic Review and Meta-Analysis.

    PubMed

    Lv, Wenshan; Du, Na; Liu, Ying; Fan, Xinyi; Wang, Yunyang; Jia, Xiujuan; Hou, Xu; Wang, Bin

    2016-05-01

    Sex steroids can positively affect the brain function, and low levels of sex steroids may be associated with worse cognitive function in the elderly men. However, previous studies reported contrary findings on the relationship between testosterone level and risk of Alzheimer's disease in the elderly men. The objective of this study was to comprehensively assess the relationship between low testosterone level and Alzheimer's disease risk in the elderly men using a meta-analysis. Only prospective cohort studies assessing the influence of low testosterone level on Alzheimer's disease risk in elderly men were considered eligible. Relative risks (RRs) with 95% confidence intervals (95% CI) were pooled to assess the risk of Alzheimer's disease in elderly men with low testosterone level. Seven prospective cohort studies with a total of 5251 elderly men and 240 cases of Alzheimer's disease were included into the meta-analysis. There was moderate degree of heterogeneity among those included studies (I(2) = 47.2%). Meta-analysis using random effect model showed that low plasma testosterone level was significantly associated with an increased risk of Alzheimer's disease in elderly men (random RR = 1.48, 95% CI 1.12-1.96, P = 0.006). Sensitivity analysis by omitting one study by turns showed that there was no obvious change in the pooled risk estimates, and all pooled RRs were statistically significant. This meta-analysis supports that low plasma testosterone level is significantly associated with increased risk of Alzheimer's disease in the elderly men. Low testosterone level is a risk factor of worse cognitive function in the elderly men.

  17. Associations of Maternal and Infant Testosterone and Cortisol Levels With Maternal Depressive Symptoms and Infant Socioemotional Problems.

    PubMed

    Cho, June; Su, Xiaogang; Phillips, Vivien; Holditch-Davis, Diane

    2016-01-01

    This study examined the associations of testosterone and cortisol levels with maternal depressive symptoms and infant socioemotional (SE) problems that are influenced by infant gender. A total of 62 mothers and their very-low-birth weight (VLBW) infants were recruited from a neonatal intensive care unit at a tertiary medical center in the southeast United States. Data were collected at three time points (before 40 weeks' postmenstrual age [PMA] and at 3 months and 6 months of age corrected for prematurity). Measures included infant medical record review, maternal interview, biochemical assays of salivary hormone levels in mother-VLBWinfant pairs, and standard questionnaires. Generalized estimating equations with separate analyses for boys and girls showed that maternal testosterone level was negatively associated with depressive symptoms in mothers of boys, whereas infant testosterone level was negatively associated with maternal report of infant SE problems in girls after controlling for characteristics of mothers and infants and number of days post birth of saliva collection. Not surprisingly, the SE problems were positively associated with a number of medical complications. Mothers with more depressive symptoms reported that their infants had more SE problems. Mothers with higher testosterone levels reported that girls, but not boys, had fewer SE problems. In summary, high levels of testosterone could have a protective role for maternal depressive symptoms and infant SE problems. Future research need to be directed toward clinical application of these preliminary results.

  18. Prenatal exposure to pesticides disrupts testicular histoarchitecture and alters testosterone levels in male Caiman latirostris.

    PubMed

    Rey, Florencia; González, Marianela; Zayas, Marcelo A; Stoker, Cora; Durando, Milena; Luque, Enrique H; Muñoz-de-Toro, Mónica

    2009-07-01

    The increased use of agrochemical pesticides, such as atrazine (ATZ) and endosulfan (END), may have a significant impact on ecosystem health and biodiversity. The aim of this study was to investigate the consequences of in ovum exposure to ATZ and END on Caiman latirostris gonadal histo-functional features. Caiman eggs were collected from environmentally pristine areas and incubated in controlled conditions at male producing temperature (33 degrees C). At stage 20 of embryonic development, the sensitive stage for gonadal sex determination, eggs were exposed to one dose of either END or ATZ. Gonadal histo-morphology was examined in caiman hatchlings and serum levels of testosterone were measured. Regardless of treatment condition, all eggs incubated at 33 degrees C resulted in male hatchlings. Tortuous seminiferous tubules with increased perimeter, disrupted distribution of peritubular myoid cells (desmin positive), and emptied tubular lumens characterized the testes of pesticide-exposed caiman. An imbalance between proliferative activity and cell death was observed in the testes of caiman exposed to the higher doses of END, mainly due to a high frequency of apoptosis in intratubular cells. This altered cell turnover was associated with decreased testosterone levels. Prenatal exposure to only one dose of END and ATZ disrupted neonatal male gonadal histo-functional features. Alterations described here could have detrimental effects on the sexual maturation of the caiman and, ultimately, on the success of male caiman reproduction.

  19. Territorial aggression, body weight, carbohydrate metabolism and testosterone levels of wild rats maintained in laboratory colonies.

    PubMed

    Lucion, A B; De-Almeida, R M; Da-Silva, R S

    1996-12-01

    Aggressive territorial behavior was studied in 15 colonies of wild rats (Rattus norvegicus), each consisting of 2 males and 1 female. One of the males attacked an intruder rat more frequently and had a higher body weight than the less aggressive one. In another experiment, male and female rats were raised in colonies from weaning to adulthood. Animals were weighed every 7 days until 90 days of age when plasma testosterone was measured in males, and plasma glucose, hepatic and muscle glycogen were measured in both males and females. THe heavier (and thus possibly dominant) males in the colonies of 3 males and 1 female also had a higher body weight than males raised with females, but without any male partner. In this long-term social relationship there were no significant differences in carbohydrate metabolism among the animals. The differential growth rate among males was established around the period of sexual maturity. Moreover, when adult, heavier males had higher plasma testosterone levels compared to the other members of the colony and also to males that had no other competitive male partner. This higher androgenic hormone level may be one of the causal factors involved in the weight increase of the dominant male in the colony.

  20. Social behavior and patterns of testosterone and glucocorticoid levels differ between male chacma and Guinea baboons.

    PubMed

    Kalbitzer, Urs; Heistermann, Michael; Cheney, Dorothy; Seyfarth, Robert; Fischer, Julia

    2015-09-01

    In multi-male, multi-female groups of mammals, males usually compete aggressively over access to females. However, species vary in the intensity of male contest competition, which has been linked to differences in testosterone and glucocorticoid profiles. Chacma (Papio ursinus) and Guinea (P. papio) baboons constitute an intriguing model to examine variation in male competition and male endocrine correlates, because of the differences in their social systems. Chacma baboons live in stable female-bonded groups with linear male dominance hierarchies and a high male mating skew, whereas Guinea baboons live in male-bonded, multi-level societies. We recorded male behavior and assayed testosterone (fT) and glucocorticoid metabolite (fGC) levels from fecal samples in one population of each species. Male chacma baboons were more frequently involved in agonistic interactions, and dominance relationships were more consistent than in Guinea baboons, where we could not detect linear hierarchies. Notably, male chacma baboons were also more aggressive towards females, indicating an overall higher aggressiveness in this species. In contrast, male Guinea baboons showed higher levels of affiliative interactions and spatial tolerance. High-ranking and consorting male chacma baboons showed elevated fGC levels and also tended to show elevated fT levels, but there was no effect of consortship in Guinea baboons. Agonism was not related to hormone levels in either species. Thus, predictors of fT and fGC levels in Guinea baboons seem to differ from chacma baboons. Our results support the view that different social systems create differential selection pressures for male aggression, reflected by different hormone profiles.

  1. Alternatives to testosterone replacement: testosterone restoration.

    PubMed

    McCullough, Andrew

    2015-01-01

    The European Male Aging Study has demonstrated that the hypogonadism of male aging is predominantly secondary. Theoretically with appropriate stimulation from the pituitary, the aging testis should be able to produce eugonadal levels of testosterone. The strategies for the treatment of late onset hypogonadism (LOH) have focused on replacement with exogenous testosterone versus restoration of endogenous production. The purpose of this article is to review existing peer-reviewed literature supporting the concept of restoration of endogenous testosterone in the treatment of LOH.

  2. Serum estradiol, progesterone, testosterone, FSH and LH levels in postmenopausal women with Alzheimer's dementia.

    PubMed

    Tsolaki, Magdalini; Grammaticos, Philip; Karanasou, Chrysanthi; Balaris, Vassilios; Kapoukranidou, Dorothea; Kalpidis, Ioannis; Petsanis, Kostas; Dedousi, Eleni

    2005-01-01

    Several studies have suggested that estrogen replacement therapy lowers the risk of Alzheimer's dementia (AD) among postmenopausal women. Other studies have evaluated serum levels of sex hormones and gonadotropins in women with AD. Estrogens (E(1) and E(2)), luteinizing hormone (LH) and follicular stimulating hormone (FSH), dihydroepiandrosterone and sex hormone binding albumin, which normally responds to circulating testosterone, have been investigated by others using the same protocol in postmenopausal women with AD, older than 65 years. Others have studied in elderly women with AD, also using one protocol, fewer sex hormones and/or gonadotropins. We have studied the serum levels of estradiol, progesterone, testosterone, LH and FSH in the same serum sample of postmenopausal women with AD and other dementias and compared them to a group of controls. We are not aware of a similar study in the literature. All patients were diagnosed on clinical grounds and screened by the mini mental score examination (MMSE). Forty eight women had AD (Group A), mean age 72 years and age range 60-84 years, s even had other types of dementia (Group B), mean age 63.5 years and age range 53-74 years and 33 women had no cognitive impairment and were studied as controls (Group C). Group C women had mean age of 65 years and their age ranged between 55-73 years. Estradiol, progesterone and testosterone were measured by radioimmunoassay (RIA), while FSH and LH by radioimmunometric assay (IRMA). Our results showed that estradiol was significantly lower in Group A as compared to Group C (P=0.04). There was no significant difference in the levels of the other four hormones in the three Groups as studied by the Mann-Whitney U and the Pearson's statistical test. Our results were not influenced by differences due to sex, age, ethnic group or education since these factors were either similar or comparable in all Groups studied. All but two of the subjects, with mild alcoholism, smoking, increased

  3. Alteration in plasma testosterone levels in male mice lacking soluble epoxide hydrolase.

    PubMed

    Luria, Ayala; Morisseau, Christophe; Tsai, Hsing-Ju; Yang, Jun; Inceoglu, Bora; De Taeye, Bart; Watkins, Steven M; Wiest, Michelle M; German, J Bruce; Hammock, Bruce D

    2009-08-01

    Soluble epoxide hydrolase (Ephx2, sEH) is a bifunctional enzyme with COOH-terminal hydrolase and NH(2)-terminal phosphatase activities. sEH converts epoxyeicosatrienoic acids (EETs) to dihydroxyeicosatrienoic acids (DHETs), and the phosphatase activity is suggested to be involved in cholesterol metabolism. EETs participate in a wide range of biological functions, including regulation of vascular tone, renal tubular transport, cardiac contractility, and inflammation. Inhibition of sEH is a potential approach for enhancing the biological activity of EETs. Therefore, disruption of sEH activity is becoming an attractive therapeutic target for both cardiovascular and inflammatory diseases. To define the physiological role of sEH, we characterized a knockout mouse colony lacking expression of the Ephx2 gene. Lack of sEH enzyme is characterized by elevation of EET to DHET ratios in both the linoleate and arachidonate series in plasma and tissues of both female and male mice. In male mice, this lack of expression was also associated with decreased plasma testosterone levels, sperm count, and testicular size. However, this genotype was still able to sire litters. Plasma cholesterol levels also declined in this genotype. Behavior tests such as anxiety-like behavior and hedonic response were also examined in Ephx2-null and WT mice, as all can be related to hormonal changes. Null mice showed a level of anxiety with a decreased hedonic response. In conclusion, this study provides a broad biochemical, physiological, and behavioral characterization of the Ephx2-null mouse colony and suggests a mechanism by which sEH and its substrates may regulate circulating levels of testosterone through cholesterol biosynthesis and metabolism.

  4. Anti-GnRH antibodies can induce castrate levels of testosterone in patients with advanced prostate cancer

    PubMed Central

    Simms, M S; Scholfield, D P; Jacobs, E; Michaeli, D; Broome, P; Humphreys, J E; Bishop, M C

    2000-01-01

    D17DT consists of the GnRH decapeptide linked to diphtheria toxoid. The aim of this pilot study was to assess the tolerance of D17DT and the production of anti-GnRH antibodies from two doses, 30 and 100 μg, in patients with locally advanced prostate cancer. Twelve patients with histologically proven prostate cancer in whom hormonal therapy was indicated were recruited. Patients received either 30 or 100 μg given intramuscularly on three separate occasions over six weeks. Patients were followed up and blood was taken for estimation of serum testosterone, PSA and anti-GnRH antibody titre. Overall the drug was well tolerated. In 5 patients a significant reduction in serum testosterone and PSA was seen. Castrate levels of testosterone were achieved in 4 and maintained for up to 9 months. Patients with the highest antibody titre had the best response in terms of testosterone suppression. This study shows that it is possible to immunize a patient with prostate cancer against GnRH to induce castrate levels of testosterone. This state appears to be reversible. This novel form of immunotherapy may have advantages over conventional forms of hormonal therapy and further studies are warranted in order to try and increase the proportion of responders. © 2000 Cancer Research Campaign PMID:10945488

  5. Ignoring the challenge? Male black redstarts (Phoenicurus ochruros) do not increase testosterone levels during territorial conflicts but they do so in response to gonadotropin-releasing hormone.

    PubMed

    Apfelbeck, Beate; Goymann, Wolfgang

    2011-11-07

    Competition elevates plasma testosterone in a wide variety of vertebrates, including humans. The 'challenge hypothesis' proposes that seasonal peaks in testosterone during breeding are caused by social challenges from other males. However, during experimentally induced male-male conflicts, testosterone increases only in a minority of songbird species tested so far. Why is this so? Comparative evidence suggests that species with a short breeding season may not elevate testosterone levels during territory defence. These species may even be limited in their physiological capability to increase testosterone levels, which can be tested by injecting birds with gonadotropin-releasing hormone (GnRH). We studied two populations of black redstarts that differ in breeding altitude, morphology and the length of their breeding season. Unexpectedly, males of neither population increased testosterone in response to a simulated territorial intrusion, but injections with GnRH resulted in a major elevation of testosterone. Thus, black redstarts would have been capable of mounting a testosterone response during the male-male challenge. Our data show, for the first time, that the absence of an androgen response to male-male challenges is not owing to physiological limitations to increase testosterone. Furthermore, in contrast to comparative evidence between species, populations of black redstarts with a long breeding season do not show the expected elevation in testosterone during male-male challenges.

  6. Men with elevated testosterone levels show more affiliative behaviours during interactions with women

    PubMed Central

    van der Meij, Leander; Almela, Mercedes; Buunk, Abraham P.; Fawcett, Tim W.; Salvador, Alicia

    2012-01-01

    Testosterone (T) is thought to play a key role in male–male competition and courtship in many vertebrates, but its precise effects are unclear. We explored whether courtship behaviour in humans is modulated and preceded by changes in T. Pairs of healthy male students first competed in a non-physical contest in which their T levels became elevated. Each participant then had a short, informal interaction with either an unfamiliar man or woman. The sex of the stimulus person did not affect the participants' behaviour overall. However, in interactions with women, those men who had experienced a greater T increase during the contest subsequently showed more interest in the woman, engaged in more self-presentation, smiled more and made more eye contact. No such effects were seen in interactions with other men. This is the first study to provide direct evidence that elevating T during male–male competition is followed by increased affiliative behaviour towards women. PMID:21632627

  7. Experimental increase of testosterone levels in free-ranging juvenile male African striped mice (Rhabdomys pumilio) induces physiological, morphological, and behavioral changes.

    PubMed

    Raynaud, Julien; Müller, Karin; Schradin, Carsten

    2012-08-01

    Testosterone influences sexual differentiation in early development, and activates sexual maturation and sex-related behavior in males during puberty. Testosterone can also influence the expression of male alternative reproductive tactics, by either organizational effects (fixed tactics) or by activational effects (plastic tactics). However, the roles of testosterone in sexual maturation and at the same time the expression of alternative reproductive tactics have been little investigated experimentally, and studies of free-ranging mammals are lacking. We conducted a field experiment in free-ranging juvenile African striped mice (Rhabdomys pumilio), a species with alternative reproductive tactics. Juvenile male striped mice reaching puberty can remain in their family as philopatric group-living males with low testosterone levels, or they can disperse and become solitary living roamers with much higher testosterone levels. We tested whether experimentally increased testosterone levels in non-scrotal juvenile males induces puberty and leads to the expression of the roaming tactic. Testosterone-treated males received the hormone for 15days by silastic implants which were empty in control-treated males. When compared to control-treated males, testosterone-treated males had higher testosterone levels, lower corticosterone levels, and became scrotal with descended testes. Testosterone-treated males also had larger testes, larger epididymides, and showed indication of spermatogenesis. Testosterone-treated males did not become solitary-living roamers, but had larger home ranges than control males. We conclude that testosterone can induce sexual maturation and causes juvenile males to increase their home ranges, maybe to search for dispersal opportunities.

  8. Housing with females increases testosterone and cortisol levels in captive groups of black-handed spider monkeys (Ateles geoffroyi).

    PubMed

    Cerda-Molina, A L; Hernández-López, L; Díaz-Díaz, G; Mejía-Varas, F; Chavira, R; Mondragón-Ceballos, R

    2012-01-01

    The black-handed spider monkey (Ateles geoffroyi) is a seasonal reproducer that requires a seclusiveness to copulate and has a fusion-fission social system. These features impose important restrictions to achieve reproduction of captive animals. We investigated if group composition in captive spider monkeys has any endocrine effects. We compared testosterone and cortisol concentrations during the mating season in all-male and multifemale-multimale groups to study if the former condition impairs reproductive potential and increases stress. Concentrations of testosterone and cortisol of males living with females were higher than those of all-male groups. In the multifemale-multimale condition, dominant males had the highest levels of testosterone, while the youngest males showed the highest concentrations of cortisol. Results show that males adjust well to isosexual grouping, this being an appropriate condition to keep animals when controlled reproduction is sought.

  9. Testosterone affects language areas of the adult human brain.

    PubMed

    Hahn, Andreas; Kranz, Georg S; Sladky, Ronald; Kaufmann, Ulrike; Ganger, Sebastian; Hummer, Allan; Seiger, Rene; Spies, Marie; Vanicek, Thomas; Winkler, Dietmar; Kasper, Siegfried; Windischberger, Christian; Swaab, Dick F; Lanzenberger, Rupert

    2016-05-01

    Although the sex steroid hormone testosterone is integrally involved in the development of language processing, ethical considerations mostly limit investigations to single hormone administrations. To circumvent this issue we assessed the influence of continuous high-dose hormone application in adult female-to-male transsexuals. Subjects underwent magnetic resonance imaging before and after 4 weeks of testosterone treatment, with each scan including structural, diffusion weighted and functional imaging. Voxel-based morphometry analysis showed decreased gray matter volume with increasing levels of bioavailable testosterone exclusively in Broca's and Wernicke's areas. Particularly, this may link known sex differences in language performance to the influence of testosterone on relevant brain regions. Using probabilistic tractography, we further observed that longitudinal changes in testosterone negatively predicted changes in mean diffusivity of the corresponding structural connection passing through the extreme capsule. Considering a related increase in myelin staining in rodents, this potentially reflects a strengthening of the fiber tract particularly involved in language comprehension. Finally, functional images at resting-state were evaluated, showing increased functional connectivity between the two brain regions with increasing testosterone levels. These findings suggest testosterone-dependent neuroplastic adaptations in adulthood within language-specific brain regions and connections. Importantly, deteriorations in gray matter volume seem to be compensated by enhancement of corresponding structural and functional connectivity. Hum Brain Mapp 37:1738-1748, 2016. © 2016 Wiley Periodicals, Inc.

  10. The association between physiologic testosterone levels, lean mass, and fat mass in a nationally representative sample of men in the United States.

    PubMed

    Mouser, J Grant; Loprinzi, Paul D; Loenneke, Jeremy P

    2016-11-01

    Testosterone deficiency leads to increased muscle loss with aging and increased fat mass. Supraphysiologic levels cause an increase in muscle mass and decrease in fat mass. The difference in lean and fat mass across physiologic levels of testosterone has been under examined in men.

  11. Dehydroepiandrosterone Supplementation Combined with Whole-Body Vibration Training Affects Testosterone Level and Body Composition in Mice

    PubMed Central

    Chen, Wen-Chyuan; Chen, Yi-Ming; Huang, Chi-Chang; Tzeng, Yen-Dun

    2016-01-01

    Dehydroepiandrosterone (DHEA), the most abundant sex steroid, is primarily secreted by the adrenal gland and a precursor hormone used by athletes for performance enhancement. Whole-body vibration (WBV) is a well-known light-resistance exercise by automatic adaptations to rapid and repeated oscillations from a vibrating platform, which is also a simple and convenient exercise for older adults. However, the potential effects of DHEA supplementation combined with WBV training on to body composition, exercise performance, and hormone regulation are currently unclear. The objective of the study is to investigate the effects of DHEA supplementation combined with WBV training on body composition, exercise performance, and physical fatigue-related biochemical responses and testosterone content in young-adult C57BL/6 mice. In this study, male C57BL/6 mice were divided into four groups (n = 8 per group) for 6-weeks treatment: sedentary controls with vehicle (SC), DHEA supplementation (DHEA, 10.2 mg/kg), WBV training (WBV; 5.6 Hz, 2 mm, 0.13 g), and WBV training with DHEA supplementation (WBV+DHEA; WBV: 5.6 Hz, 2 mm, 0.13 g and DHEA: 10.2 mg/kg). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time, as well as changes in body composition and anti-fatigue levels of serum lactate, ammonia, glucose, creatine kinase (CK), and blood urea nitrogen (BUN) after a 15-min swimming exercise. In addition, the biochemical parameters and the testosterone content were measured at the end of the experiment. Six-week DHEA supplementation alone significantly increased mice body weight (BW), muscle weight, testosterone level, and glycogen contents (liver and muscle) when compared with SC group. DHEA supplementation alone had no negative impact on all tissue and biochemical profiles, but could not improve exercise performance. However, WBV+DHEA supplementation also significantly decreased BW, testosterone level and glycogen content of liver, as well as serum

  12. Dehydroepiandrosterone Supplementation Combined with Whole-Body Vibration Training Affects Testosterone Level and Body Composition in Mice.

    PubMed

    Chen, Wen-Chyuan; Chen, Yi-Ming; Huang, Chi-Chang; Tzeng, Yen-Dun

    2016-01-01

    Dehydroepiandrosterone (DHEA), the most abundant sex steroid, is primarily secreted by the adrenal gland and a precursor hormone used by athletes for performance enhancement. Whole-body vibration (WBV) is a well-known light-resistance exercise by automatic adaptations to rapid and repeated oscillations from a vibrating platform, which is also a simple and convenient exercise for older adults. However, the potential effects of DHEA supplementation combined with WBV training on to body composition, exercise performance, and hormone regulation are currently unclear. The objective of the study is to investigate the effects of DHEA supplementation combined with WBV training on body composition, exercise performance, and physical fatigue-related biochemical responses and testosterone content in young-adult C57BL/6 mice. In this study, male C57BL/6 mice were divided into four groups (n = 8 per group) for 6-weeks treatment: sedentary controls with vehicle (SC), DHEA supplementation (DHEA, 10.2 mg/kg), WBV training (WBV; 5.6 Hz, 2 mm, 0.13 g), and WBV training with DHEA supplementation (WBV+DHEA; WBV: 5.6 Hz, 2 mm, 0.13 g and DHEA: 10.2 mg/kg). Exercise performance was evaluated by forelimb grip strength and exhaustive swimming time, as well as changes in body composition and anti-fatigue levels of serum lactate, ammonia, glucose, creatine kinase (CK), and blood urea nitrogen (BUN) after a 15-min swimming exercise. In addition, the biochemical parameters and the testosterone content were measured at the end of the experiment. Six-week DHEA supplementation alone significantly increased mice body weight (BW), muscle weight, testosterone level, and glycogen contents (liver and muscle) when compared with SC group. DHEA supplementation alone had no negative impact on all tissue and biochemical profiles, but could not improve exercise performance. However, WBV+DHEA supplementation also significantly decreased BW, testosterone level and glycogen content of liver, as well as serum

  13. Seasonal changes in testosterone and corticosterone levels in four social classes of a desert dwelling sociable rodent.

    PubMed

    Schradin, Carsten

    2008-04-01

    Animals have to adjust their physiology to seasonal changes, in response to variation in food availability, social tactics and reproduction. I compared basal corticosterone and testosterone levels in free ranging striped mouse from a desert habitat, comparing between the sexes, breeding and philopatric non-breeding individuals, and between the breeding and the non-breeding season. I expected differences between breeders and non-breeders and between seasons with high and low food availability. Basal serum corticosterone was measured from 132 different individuals and serum testosterone from 176 different individuals of free living striped mice. Corticosterone and testosterone levels were independent of age, body weight and not influenced by carrying a transmitter. The levels of corticosterone and testosterone declined by approximately 50% from the breeding to the non-breeding season in breeding females as well as non-breeding males and females. In contrast, breeding males showed much lower corticosterone levels during the breeding season than all other classes, and were the only class that showed an increase of corticosterone from the breeding to the non-breeding season. As a result, breeding males had similar corticosterone levels as other social classes during the non-breeding season. During the breeding season, breeding males had much higher testosterone levels than other classes, which decreased significantly from the breeding to the non-breeding season. My results support the prediction that corticosterone decreases during periods of low food abundance. Variation in the pattern of hormonal secretion in striped mice might assist them to cope with seasonal changes in energy demand in a desert habitat.

  14. Female major histocompatibility complex type affects male testosterone levels and sperm number in the horse (Equus caballus)

    PubMed Central

    Burger, D.; Dolivo, G.; Marti, E.; Sieme, H.; Wedekind, C.

    2015-01-01

    Odours of vertebrates often contain information about the major histocompatibility complex (MHC), and are used in kin recognition, mate choice or female investment in pregnancy. It is, however, still unclear whether MHC-linked signals can also affect male reproductive strategies. We used horses (Equus caballus) to study this question under experimental conditions. Twelve stallions were individually exposed either to an unfamiliar MHC-similar mare and then to an unfamiliar MHC-dissimilar mare, or vice versa. Each exposure lasted over a period of four weeks. Peripheral blood testosterone levels were determined weekly. Three ejaculates each were collected in the week after exposure to both mares (i.e. in the ninth week) to determine mean sperm number and sperm velocity. We found high testosterone levels when stallions were kept close to MHC-dissimilar mares and significantly lower ones when kept close to MHC-similar mares. Mean sperm number per ejaculate (but not sperm velocity) was positively correlated to mean testosterone levels and also affected by the order of presentation of mares: sperm numbers were higher if MHC-dissimilar mares were presented last than if MHC-similar mares were presented last. We conclude that MHC-linked signals influence testosterone secretion and semen characteristics, two indicators of male reproductive strategies. PMID:25904670

  15. Female major histocompatibility complex type affects male testosterone levels and sperm number in the horse (Equus caballus).

    PubMed

    Burger, D; Dolivo, G; Marti, E; Sieme, H; Wedekind, C

    2015-05-22

    Odours of vertebrates often contain information about the major histocompatibility complex (MHC), and are used in kin recognition, mate choice or female investment in pregnancy. It is, however, still unclear whether MHC-linked signals can also affect male reproductive strategies. We used horses (Equus caballus) to study this question under experimental conditions. Twelve stallions were individually exposed either to an unfamiliar MHC-similar mare and then to an unfamiliar MHC-dissimilar mare, or vice versa. Each exposure lasted over a period of four weeks. Peripheral blood testosterone levels were determined weekly. Three ejaculates each were collected in the week after exposure to both mares (i.e. in the ninth week) to determine mean sperm number and sperm velocity. We found high testosterone levels when stallions were kept close to MHC-dissimilar mares and significantly lower ones when kept close to MHC-similar mares. Mean sperm number per ejaculate (but not sperm velocity) was positively correlated to mean testosterone levels and also affected by the order of presentation of mares: sperm numbers were higher if MHC-dissimilar mares were presented last than if MHC-similar mares were presented last. We conclude that MHC-linked signals influence testosterone secretion and semen characteristics, two indicators of male reproductive strategies.

  16. Testosterone Buccal

    MedlinePlus

    ... depending on the amount of testosterone in your blood during your treatment.Testosterone buccal systems may control your condition but will not cure it. Continue to use testosterone even if you feel well. Do not stop using testosterone without talking to your doctor. If ...

  17. Reactive oxygen species: players in the cardiovascular effects of testosterone.

    PubMed

    Tostes, Rita C; Carneiro, Fernando S; Carvalho, Maria Helena C; Reckelhoff, Jane F

    2016-01-01

    Androgens are essential for the development and maintenance of male reproductive tissues and sexual function and for overall health and well being. Testosterone, the predominant and most important androgen, not only affects the male reproductive system, but also influences the activity of many other organs. In the cardiovascular system, the actions of testosterone are still controversial, its effects ranging from protective to deleterious. While early studies showed that testosterone replacement therapy exerted beneficial effects on cardiovascular disease, some recent safety studies point to a positive association between endogenous and supraphysiological levels of androgens/testosterone and cardiovascular disease risk. Among the possible mechanisms involved in the actions of testosterone on the cardiovascular system, indirect actions (changes in the lipid profile, insulin sensitivity, and hemostatic mechanisms, modulation of the sympathetic nervous system and renin-angiotensin-aldosterone system), as well as direct actions (modulatory effects on proinflammatory enzymes, on the generation of reactive oxygen species, nitric oxide bioavailability, and on vasoconstrictor signaling pathways) have been reported. This mini-review focuses on evidence indicating that testosterone has prooxidative actions that may contribute to its deleterious actions in the cardiovascular system. The controversial effects of testosterone on ROS generation and oxidant status, both prooxidant and antioxidant, in the cardiovascular system and in cells and tissues of other systems are reviewed.

  18. Reactive oxygen species: players in the cardiovascular effects of testosterone

    PubMed Central

    Carneiro, Fernando S.; Carvalho, Maria Helena C.; Reckelhoff, Jane F.

    2015-01-01

    Androgens are essential for the development and maintenance of male reproductive tissues and sexual function and for overall health and well being. Testosterone, the predominant and most important androgen, not only affects the male reproductive system, but also influences the activity of many other organs. In the cardiovascular system, the actions of testosterone are still controversial, its effects ranging from protective to deleterious. While early studies showed that testosterone replacement therapy exerted beneficial effects on cardiovascular disease, some recent safety studies point to a positive association between endogenous and supraphysiological levels of androgens/testosterone and cardiovascular disease risk. Among the possible mechanisms involved in the actions of testosterone on the cardiovascular system, indirect actions (changes in the lipid profile, insulin sensitivity, and hemostatic mechanisms, modulation of the sympathetic nervous system and renin-angiotensin-aldosterone system), as well as direct actions (modulatory effects on proinflammatory enzymes, on the generation of reactive oxygen species, nitric oxide bioavailability, and on vasoconstrictor signaling pathways) have been reported. This mini-review focuses on evidence indicating that testosterone has prooxidative actions that may contribute to its deleterious actions in the cardiovascular system. The controversial effects of testosterone on ROS generation and oxidant status, both prooxidant and antioxidant, in the cardiovascular system and in cells and tissues of other systems are reviewed. PMID:26538238

  19. [Low-dose desmopressin (DDAVP) and blood levels of FSH, LH and testosterone in men].

    PubMed

    García-Pascual, I J; Rozán Flores, M A

    1996-03-01

    The effect of desmopressin (DDAVP) administration (2.5 micrograms/12 hours) on serum concentrations of FSH, LH and testosterone was studied in six men. No significant changes were observed in serum concentrations of FSH and LH after 9 days with DDAVP therapy. Nevertheless, serum concentrations of testosterone after 12 hours of DDAVP administration were significantly higher than basal concentrations. Three hours after the administration of DDAVP, serum testosterone concentrations decreased significantly. The conclusion reached was that low doses of desmopressin do not change serum concentrations of FSH and LH, but serum concentration of testosterone is decreased within three hours after the administration, although an increase is observed 12 hours later possibly due to a "rebound effect". Desmopressin would therefore directly act upon human testicle.

  20. Establishing the Biological Relevance of Dipentyl Phthalate Reductions in Fetal Rat Testosterone Production and Plasma and Testis Testosterone Levels

    EPA Science Inventory

    Phthalate esters (PEs) constitute a large class of compounds that are used for many consumer product applications. Many of the C2-C7 di-ortho PEs reduce fetal testicular hormone and gene expression levels in rats resulting in adverse effects seen later in life but it appears that...

  1. Paternal retrievals increase testosterone levels in both male and female California mouse (Peromyscus californicus) offspring.

    PubMed

    Chary, Mamatha C; Cruz, Jayson P; Bardi, Massimo; Becker, Elizabeth A

    2015-07-01

    The importance of maternal care on offspring development has received considerable attention, although more recently, researchers have begun to focus on the significance of paternal contributions. In the monogamous and bi-parental California mouse, fathers provide high levels of care, and therefore serve as a model system for studying paternal effects on behavior and underlying neuroendocrine mechanisms. Paternal retrievals in this species influence long term changes in brain (expression of arginine vasopressin-AVP) and behavior (aggression and parenting) in adult male offspring. Further, paternal retrievals induce a transient increase in testosterone (T) in male offspring, which is thought to mediate the relationship between paternal retrievals and AVP expression. Although the father-son relationship has been well characterized, few studies have examined father-daughter interactions. In California mice, paternal retrievals increase aggression in female offspring. Although T has been implicated in the regulation of female aggression, it remains unclear whether T may underlie long-term changes in female offspring aggression in response to paternal retrievals. In the current study, we examined the influence of paternal retrievals on T in both male and female offspring. Retrievals were manipulated experimentally by displacement of the pup and trunk blood was collected from retrieved, non-retrieved, and non-manipulated (baseline) pups. We found that fathers expressed similar levels of retrievals towards sons and daughters, and that T levels were elevated in retrieved, as compared to non-retrieved offspring. Similar to what has been previously described in male offspring and replicated here, female offspring that were retrieved had higher T levels than non-retrieved females. Neither females nor males experienced a change in corticosterone levels in response to retrievals suggesting offspring do not mount a stress response to paternal care. Therefore, our data suggest

  2. Establishing the “Biological Relevance” of Dipentyl Phthalate Reductions in Fetal Rat Testosterone Production and Plasma and Testis Testosterone Levels

    PubMed Central

    Gray, Leon Earl; Furr, Johnathan; Tatum-Gibbs, Katoria R.; Lambright, Christy; Sampson, Hunter; Hannas, Bethany R.; Wilson, Vickie S.; Hotchkiss, Andrew; Foster, Paul M. D.

    2016-01-01

    Phthalate esters (PEs) constitute a large class of compounds that are used for many consumer product applications. Many of the C2–C7 di-ortho PEs reduce fetal testicular hormone and gene expression levels in rats resulting in adverse effects seen later in life but it appears that relatively large reductions in fetal testosterone (T) levels and testis gene expression may be required to adversely affect reproductive development (Hannas, B. R., Lambright, C. S., Furr, J., Evans, N., Foster, P. M., Gray, E. L., and Wilson, V. S. (2012). Genomic biomarkers of phthalate-induced male reproductive developmental toxicity: a targeted RT-PCR array approach for defining relative potency. Toxicol. Sci. 125, 544–557). The objectives of this study were (1) to model the relationships between changes in fetal male rat plasma testosterone (PT), T levels in the testis (TT), T production (PROD), and testis gene expression with the reproductive malformation rates, and (2) to quantify the “biologically relevant reductions” (BRRs) in fetal T necessary to induce adverse effects in the offspring. In the fetal experiment, Harlan Sprague-Dawley rats were dosed with dipentyl phthalate (DPeP) at 0, 11, 33, 100, and 300 mg/kg/day from gestational days (GD) 14–18 and fetal testicular T, PT levels, and T Prod and gene expression were assessed on GD 18. In the postnatal experiment, rats were dosed with DPeP from GD 8–18 and reproductive development was monitored through adulthood. The dose-response curves for TT levels (ED50 = 53 mg/kg) and T PROD (ED50 = 45 mg/kg) were similar, whereas PT was reduced at ED50 = 19 mg/kg. When the reductions in TPROD and Insl3 mRNA were compared with the postnatal effects of in utero DPeP, dose-related reproductive alterations were noted when T PROD and Insl3 mRNA were reduced by >45% and 42%, respectively. The determination of BRR levels may enable risk assessors to utilize fetal endocrine data to help establish points of departure for

  3. Compounded Testosterone Troches TO OPTIMIZE HEALTH AND THE TESTOSTERONE CONTROVERSY.

    PubMed

    Guth, Michael A S

    2015-01-01

    As men age, testosterone levels progressively fall and inflammatory biomarkers increase. The gradual decline in testosterone production with aging, known as andropause, is common and may have deleterious effects on men including decreased overall well-being, increased sarcopenia, increased risk of cardiovascular disease, reduced sexual function, and bone loss. Therefore, it comes as no surprise that an increasing number of men worldwide have begun requesting testosterone replacement therapy from their physicians. Occasionally, physicians discourage male patients from getting testosterone replacement therapy based on a few recent studies indicating the therapy causes cardiovascular events, including myocardial infarctions. Yet, an extensive review of the testosterone replacement therapy literature reveals that the majority of clinical studies show that properly administered testosterone replacement therapy, in which estradiol and dihydrotestosterone levels are also controlled, has no adverse effects on myocardial infarction risk. The current state-of-the-art in testosterone replacement therapy comprises compounded testosterone troches; an aromatase inhibitor, such as generic Anastrazole, to control estradiol levels; and a 5α-reductase inhibitor, such as beneric Dutasteride or Finasteride, to control dihydrotestosterone. Compounded testosterone troches easily raise serum testosterone levels to the optimal range, are highly cost effective at $82 for a 180-day supply, and provide affordable access to testosterone replacement therapy to millions of men requesting it. Yet, the Blue Cross Blue Shield-associated firms have largely denied requests for coverage of compounded medications, including testosterone troches. Despite data demonstrating strong links between testosterone deficiency and significant comorbid conditions (including Type 2 diabetes and other metabolic syndrome diseases) as well as the health benefits of testosterone replacement therapy, some physian have

  4. Significant increase of salivary testosterone levels after single therapeutic transdermal administration of testosterone: suitability as a potential screening parameter in doping control.

    PubMed

    Thieme, Detlef; Rautenberg, Claudia; Grosse, Joachim; Schoenfelder, Martin

    2013-01-01

    The legally defensible proof of the abuse of endogenous steroids in sports is currently based on carbon isotope ratio mass spectrometry (IRMS), i.e. a comparison between (13)C/(12)C ratios of diagnostic precursors and metabolites of testosterone. The application of this technique requires a chromatographic baseline separation of respective steroids prior to IRMS detection and hence laborious sample pre-processing of the urinary steroid extracts including clean up by solid-phase extraction and/or liquid chromatography. Consequently, an efficient pre-selection of suspicious control urine samples is essential for appropriate follow up confirmation by IRMS and effective doping control. Two single transdermal administration studies of testosterone (50 mg Testogel® and Testopatch® at 3.8 mg in 16 h, respectively) were conducted and resulting profiles of salivary testosterone and urinary steroid profiles and corresponding carbon isotope ratios were determined. Conventional doping control markers (testosterone/epitestosterone ratio, threshold concentrations of androsterone, etiocholanolone, or androstanediols) did not approach or exceed critical thresholds. In contrast to these moderate variations, the testosterone concentration in oral fluid increased from basal values (30-142 pg/mg) to peak concentrations above 1000 pg/mg. It is likely that this significant increase in oral fluid is due to a pulsatile elevation of free (protein unbound) circulating testosterone after transdermal administration and may be assumed to represent a more diagnostic marker for transdermal testosterone administration.

  5. Moderating effects of salivary testosterone levels on associations between job demand and psychological stress response in Japanese medical workers

    PubMed Central

    HIROKAWA, Kumi; MIWA, Machiko; TANIGUCHI, Toshiyo; TSUCHIYA, Masao; KAWAKAMI, Norito

    2015-01-01

    Levels of job stress have been shown to be inversely associated with testosterone levels, but some inconsistent results have been documented. We investigated the moderating effects of testosterone levels on associations between job stress-factors and psychological stress responses in Japanese medical workers. The participants were 63 medical staff (20 males and 43 women; mean age: 30.6 years; SD=7.3) in Okayama, Japan. Their job-stress levels and psychological stress responses were evaluated using self-administered questionnaires, and their salivary testosterone collected. Multiple regression analyses showed that job demand was positively associated with stress responses in men and women. An interaction between testosterone and support from colleagues had a significant effect on depression and anxiety for women. In women with lower testosterone levels, a reducing effect of support from colleagues on depression and anxiety was intensified. In women with higher testosterone levels, depression and anxiety levels were identical regardless of support from colleagues. Testosterone may function as a moderator between perceived work environment and psychological stress responses for female medical workers. PMID:26632120

  6. Time-related increase in urinary testosterone levels and stable semen analysis parameters after bariatric surgery in men.

    PubMed

    Legro, Richard S; Kunselman, Allen R; Meadows, Juliana W; Kesner, James S; Krieg, Edward F; Rogers, Ann M; Cooney, Robert N

    2015-02-01

    The aim of this prospective cohort study was to determine the time-course in androgen and semen parameters in men after weight loss associated with bariatric surgery. Six men aged 18-40 years, meeting National Institutes of Health bariatric surgery guidelines, were followed between 2005 and 2008. Study visits took place at baseline, then 1, 3, 6 and 12 months after surgery. All men underwent Roux-en-y gastric bypass (RYGB). At each visit, biometric, questionnaire, serum, and urinary specimens and seman analysis were collected. Urinary integrated total testosterone levels increased significantly (P < 0.0001) by 3 months after surgery, and remained elevated throughout the study. Circulating testosterone levels were also higher at 1 and 6 months after surgery, compared with baseline. Serum sex hormone-binding globulin levels were significantly elevated at all time points after surgery (P < 0.01 to P = 0.02). After RYGB surgery, no significant changes occurred in urinary oestrogen metabolites (oestrone 3-glucuronide), serum oestradiol levels, serial semen parameters or male sexual function by questionnaire. A threshold of weight loss is necessary to improve male reproductive function by reversing male hypogonadism, manifested as increased testosterone levels. Further serial semen analyses showed normal ranges for most parameters despite massive weight loss.

  7. Early follicular testosterone level predicts preference for masculinity in male faces - but not for women taking hormonal contraception.

    PubMed

    Bobst, Cora; Sauter, Sabine; Foppa, Andrina; Lobmaier, Janek S

    2014-03-01

    It has been shown that women's preference for masculinity in male faces changes across the menstrual cycle. Preference for masculinity is stronger when conception probability is high than when it is low. These findings have been linked to cyclic fluctuations of hormone levels. The purpose of the present study is to further investigate the link between gonadal steroids (i.e. testosterone, estradiol, and progesterone) and masculinity preference in women, while holding the cycle phase constant. Sixty-two female participants were tested in their early follicular cycle phase, when conception probability is low. Participants were shown face pairs and where asked to choose the more attractive face. Face pairs consisted of a masculinized and feminized version of the same face. For naturally cycling women we found a positive relationship between saliva testosterone levels and masculinity preference, but there was no link between any hormones and masculinity preference for women taking hormonal contraception. We conclude that in naturally cycling women early follicular testosterone levels are associated with masculinity preference. However, these hormonal links were not found for women with artificially modified hormonal levels, that is, for women taking hormonal contraception.

  8. Elevated testosterone levels in a racing horse due to an XY testicular disorder of sexual development.

    PubMed

    Dierks, Claudia; Sieme, Harald; Piechotta, Marion; Lehner, Stephanie; Merkt, Jan Carlos; Uphaus, Hubert; Klug, Erich; Distl, Ottmar

    2015-01-01

    A female thoroughbred successful in horse racing was positively tested for high testosterone values. This horse neither showed stallion-like-behaviour nor signs of ambiguous external genitalia. The karyotype of this horse was 2n = 64,XY and the sex-determining region of Y (SRY) PCR was positive. Hair samples tested for naturally testosterone revealed values normal for stallions, and tests for eight synthetic testosterone esters remained negative. The phenotype, ultrasonographic examination, hormone status, cytogenetic evaluation and molecular diagnostics lead to the diagnosis of an XY testicular disorder of sexual development (DSD) due to a complete androgen insensitivity syndrome. To our knowledge this is the first report about a thoroughbred in racing sports with an XY testicular disorder of sexual development. To date, intersex racing horses have never been described in thoroughbreds or a regulation for intersexes in regard to horse races has been issued.

  9. Urinary testosterone-metabolite levels and dominance rank in male and female bonobos (Pan paniscus).

    PubMed

    Sannen, Adinda; Van Elsacker, Linda; Heistermann, Michael; Eens, Marcel

    2004-04-01

    The correlation between testosterone (T) and dominance rank may vary among species, and is expected to become stronger as the importance of aggressive competition for rank increases. However, it may also vary among social situations within a species, showing a stronger correlation during socially unstable periods. Knowledge on this topic in great apes, especially in females, is scant. This study presents the first data on the relationship between T and dominance rank in both sexes of the bonobo ( Pan paniscus). For each period (four socially unstable and two stable ones), linear rank orders were determined and subsequently correlated with the accompanying mean urinary T-metabolite concentrations (measured as immunoreactive 5alpha-androstan-17alpha-ol-3-one). No correlation between these two variables was found for either sex among individuals during socially unstable or stable periods. Also, within an individual over the six periods, no relationship of T with rank could be demonstrated. These results suggest that either the outcomes of aggressions have no influence on T levels, or such clear outcomes appear insufficiently frequent to affect T levels over longer periods. Even during the unstable periods, the rate of aggressions was not higher than during stable periods, suggesting that frequencies of aggression have little effect on rank. Further analyses indeed demonstrated no correlation between frequencies of overall aggressions or any type of aggressive behavior separately, or rank. Perhaps factors other than the frequency of displayed aggressions alone have a marked influence on a bonobo's rank, for example, coalition partners. Overall, in bonobos, T apparently does not form a physiological reflection of social status.

  10. Testosterone Topical

    MedlinePlus

    ... eyes, wash them right away with warm, clean water. Call a doctor if your eyes become irritated.Testosterone topical comes in single use tubes and packets and a multiple use pump. The pump releases a specific amount of testosterone ...

  11. Testosterone affects language areas of the adult human brain

    PubMed Central

    Hahn, Andreas; Kranz, Georg S.; Sladky, Ronald; Kaufmann, Ulrike; Ganger, Sebastian; Hummer, Allan; Seiger, Rene; Spies, Marie; Vanicek, Thomas; Winkler, Dietmar; Kasper, Siegfried; Windischberger, Christian; Swaab, Dick F.

    2016-01-01

    Abstract Although the sex steroid hormone testosterone is integrally involved in the development of language processing, ethical considerations mostly limit investigations to single hormone administrations. To circumvent this issue we assessed the influence of continuous high‐dose hormone application in adult female‐to‐male transsexuals. Subjects underwent magnetic resonance imaging before and after 4 weeks of testosterone treatment, with each scan including structural, diffusion weighted and functional imaging. Voxel‐based morphometry analysis showed decreased gray matter volume with increasing levels of bioavailable testosterone exclusively in Broca's and Wernicke's areas. Particularly, this may link known sex differences in language performance to the influence of testosterone on relevant brain regions. Using probabilistic tractography, we further observed that longitudinal changes in testosterone negatively predicted changes in mean diffusivity of the corresponding structural connection passing through the extreme capsule. Considering a related increase in myelin staining in rodents, this potentially reflects a strengthening of the fiber tract particularly involved in language comprehension. Finally, functional images at resting‐state were evaluated, showing increased functional connectivity between the two brain regions with increasing testosterone levels. These findings suggest testosterone‐dependent neuroplastic adaptations in adulthood within language‐specific brain regions and connections. Importantly, deteriorations in gray matter volume seem to be compensated by enhancement of corresponding structural and functional connectivity. Hum Brain Mapp 37:1738–1748, 2016. © 2016 Wiley Periodicals, Inc. PMID:26876303

  12. Testosterone and Occupational Achievement.

    ERIC Educational Resources Information Center

    Dabbs, James M., Jr.

    1992-01-01

    Archival data on 4,462 military veterans linked higher levels of serum testosterone to lower-status occupations. A structural equation model was supported in which higher testosterone, mediated through lower intellectual ability, greater antisocial behavior, and lower education, leads away from white-collar occupations. Contains 49 references.…

  13. Effect of Lepidium meyenii (MACA) on sexual desire and its absent relationship with serum testosterone levels in adult healthy men.

    PubMed

    Gonzales, G F; Córdova, A; Vega, K; Chung, A; Villena, A; Góñez, C; Castillo, S

    2002-12-01

    This study was a 12-week double blind placebo-controlled, randomized, parallel trial in which active treatment with different doses of Maca Gelatinizada was compared with placebo. The study aimed to demonstrate if effect of Maca on subjective report of sexual desire was because of effect on mood or serum testosterone levels. Men aged 21-56 years received Maca in one of two doses: 1,500 mg or 3,000 mg or placebo. Self-perception on sexual desire, score for Hamilton test for depression, and Hamilton test for anxiety were measured at 4, 8 and 12 weeks of treatment. An improvement in sexual desire was observed with Maca since 8 weeks of treatment. Serum testosterone and oestradiol levels were not different in men treated with Maca and in those treated with placebo (P:NS). Logistic regression analysis showed that Maca has an independent effect on sexual desire at 8 and 12 weeks of treatment, and this effect is not because of changes in either Hamilton scores for depression or anxiety or serum testosterone and oestradiol levels. In conclusion, treatment with Maca improved sexual desire.

  14. Changes in Men's Salivary Testosterone and Cortisol Levels, and in Sexual Desire after Smelling Female Axillary and Vulvar Scents.

    PubMed

    Cerda-Molina, Ana Lilia; Hernández-López, Leonor; de la O, Claudio E; Chavira-Ramírez, Roberto; Mondragón-Ceballos, Ricardo

    2013-01-01

    Several studies have shown that a woman's vaginal or axillary odors convey information on her attractivity. Yet, whether such scents induce psychoneuroendocrinological changes in perceivers is still controversial. We studied if smelling axillary and vulvar odors collected in the periovulatory and late luteal phases of young women modify salivary testosterone and cortisol levels, as well as sexual desire in men. Forty-five women and 115 men, all of them college students and unacquainted with each other, participated in the study. Female odors were collected on pads affixed to the axilla and on panty protectors both worn the entire night before experiments. Men provided five saliva samples, a basal one before the smelling procedure, and four more 15, 30, 60, and 75 min after exposure to odors. Immediately after smelling the odor source, men answered a questionnaire rating hedonic qualities of scents, and after providing the last saliva sample they answered questionnaire on sexual desire. We found that periovulatory axillary and vulvar odors increased testosterone and cortisol levels, with vulvar scents producing a more prolonged effect. Luteal axilla odors decreased testosterone and cortisol levels, while luteal vulva odors increased cortisol. Periovulatory axilla and vulva scents accounted for a general increase of interest in sex. These odors were also rated as more pleasant and familiar, while luteal vulvar odors were perceived as intense and unpleasant.

  15. Prevalence of low testosterone levels in men with type 2 diabetes mellitus: a cross-sectional study

    PubMed Central

    Al Hayek, Ayman A.; Khader, Yousef S.; Jafal, Sahar; Khawaja, Nahla; Robert, Asirvatham A.; Ajlouni, Kamel

    2013-01-01

    Background: A high prevalence of low serum testosterone (LST) in men with type 2 diabetes have been reported worldwide. The aim of this study was to determine the prevalence and associated factors of LST in men with type 2 diabetes. Materials and Methods: This was a cross-sectional study, conducted among 1,089 men (aged 30-70 years) with type 2 diabetes who consecutively attended a major diabetes center in Amman, Jordan, between August 2008 and February 2009. The patients’ demographic characteristics were collected using a prestructured questionnaire. Duration of diabetes, smoking habits, presence of retinopathy, neuropathy, and nephropathy were collected from the medical records. All participants were asked to complete the Androgen Deficiency in Ageing Male (ADAM) questionnaire. Venous blood sample was collected to test for total testosterone (TT), free testosterone (FT), sex hormone binding globulin (SHBG), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), serum lipids, and glycosylated hemoglobin (HbA1c). LST was defined as TT <3 ng/ml. Results: Overall, 36.5% of patients with diabetes had TT level <3 ng/ml and 29% had symptoms of androgen deficiency. Of those with serum testosterone level <3 ng/ml, 80.2% had symptoms of androgen deficiency, 16.9% had primary hypogonadism (HG), and 83.1% had secondary HG. Univariate analysis showed a significant relationship between age, income, education, body mass index (BMI), smoking, duration of diabetes, diabetic nephropathy, diabetic neuropathy, and HbA1c. Multivariate logistic regression analysis indicated age, income, BMI, and diabetic neuropathy as the independent risk factors of LST. Conclusions: The prevalence of LST among men with type 2 diabetes is high. Age, income, BMI, and diabetic neuropathy were found to be the independent risk factors for LST. PMID:24672276

  16. Testosterone regulates levels of cystic fibrosis transmembrane regulator, adenylate cyclase, and cAMP in the seminal vesicles of orchidectomized rats.

    PubMed

    Ramli, Nur Siti Khadijah; Giribabu, Nelli; Muniandy, Sekaran; Salleh, Naguib

    2016-01-15

    Secretions of chloride (Cl(-))- and bicarbonate (HCO3(-))-rich fluid by the seminal vesicles could involve cystic fibrosis transmembrane regulator (CFTR), which activity can be stimulated by cAMP generated from the reaction involving adenylate cyclase (AC). In this study, we investigated levels of CFTR, AC, and cAMP in the seminal vesicles under testosterone influence. Orchidectomized adult male rats received 7-day treatment with 125 or 250 μg/kg/day of testosterone with or without flutamide or finasteride. At the end of the treatment, animals were sacrificed and seminal vesicles were harvested for analyses of CFTR and AC protein expression level by Western blotting. Distribution of CFTR and AC in seminal vesicles was observed by immunohistochemistry. Levels of cAMP and dihydrotestosterone in seminal vesicle homogenates were measured by ELISA. Cystic fibrosis transmembrane regulator, AC, and cAMP levels increased with increasing doses of testosterone (P < 0.05 compared to nontreated orchidectomized rats). Cystic fibrosis transmembrane regulator and AC were expressed at the apical membrane of the epithelium lining the seminal vesicle lumen with higher expression levels observed in testosterone-treated rats than in non-treated orchidectomized rats (P < 0.05). The inhibitory effects of flutamide or finasteride on these parameters were greater in 250 μg/kg/day testosterone-treated rats than their effects in 125 μg/kg/day testosterone-treated rats. Higher dihydrotestosterone levels were observed in seminal vesicle homogenates after treatment with 250 μg/kg/day than with 125 μg/kg/day of testosterone (P < 0.05). Increased levels of CFTR, AC, and cAMP in seminal vesicles might contribute toward an increase in Cl(-) and HCO3(-) concentrations in the seminal fluid as reported under testosterone influence.

  17. Testosterone and musical talent.

    PubMed

    Hassler, M

    1991-01-01

    Two recently published hypotheses on the biological basis of special talents are discussed in relation to experimental data obtained from musical composers, instrumentalists, painters, and non-musicians, and from adolescent boys and girls with different levels of musical capacities. Both hypotheses assign an important influence to prenatal testosterone effects on the developing brain. Geschwind and Galaburda (1985) predict that subjects with special talents may have anomalous hemispheric dominance for verbal material. This was confirmed experimentally in adolescents and in adults using a dichotic listening task to assess functional lateralization. Hassler and Nieschlag (1989) expect musicians of both sexes to be psychologically androgynous and to have current testosterone levels that differ from sex-typed males and females. Salivary testosterone was measured in adults and in adolescents. Creative musical behavior was associated with very low testosterone values in males, and with high testosterone levels in females. Sexual activity level and motivation did not differ between males with testosterone levels less than or equal to 200 pmol/l and those with greater than 220 pmol/l. We tentatively suggest from our data that, among a complex interaction of biological and social factors, an optimal testosterone range may exist for the expression of creative musical behavior. Exceeding the range in the course of adolescence may be detrimental for musical creativity in boys.

  18. Changes in testosterone and dihydrotestosterone levels in male rat accessory sex organs, serum, and seminal fluid after castration: establishment of a new highly sensitive simultaneous androgen measurement method.

    PubMed

    Kashiwagi, Bunzo; Shibata, Yasuhiro; Ono, Yoshihiro; Suzuki, Ryota; Honma, Seijiro; Suzuki, Kazuhiro

    2005-01-01

    It is known that abnormal androgen dynamics in the tissues is a cause of androgen-dependent disorders. Investigation of tissue androgen levels could provide a clue to the elucidation of disorders. However, it is difficult to measure a trace amount of androgen in the tissues. We established a highly sensitive simultaneous quantification method of testosterone and dihydrotestosterone (DHT), which play the most important roles in the body among androgenic steroids in trace amounts, and investigated time course changes in testosterone and DHT levels in male accessory sex organs, serum, and seminal fluid after castration in rat models. In addition, changes in the testosterone/DHT ratio of male accessory sex organs and seminal fluid were observed. The simultaneous testosterone and DHT measurement method established by us was validated. Intra-assay variation and interassay precision and accuracy were all within +/-20%, and the quantification limits of testosterone and DHT were both 15.6 pg/g. With the use of this method, the testosterone and DHT levels in the prostate, seminal vesicles, and serum immediately after castration were similar to those previously reported. The testosterone and DHT levels were 350 pg/g and 605 pg/g, respectively; which showed dominance of DHT in seminal fluid, although it was not as marked as that in the male accessory sex organs. Androgens decreased with time after castration in the accessory sex organs, serum, and seminal fluid. In the prostate and seminal vesicles, testosterone and DHT decreased to about 50% and about 2% of the normal levels, respectively, 72 hours after castration. The serum levels were under the quantification limits 6 hours after castration and thereafter. In seminal fluid, the testosterone and DHT levels decreased to 49% and 35% of normal levels, respectively, 72 hours after castration. The testosterone/DHT ratio in the male accessory sex organs was lower in the prostate (0.06) than in the seminal vesicles (0

  19. Do evolutionary life-history trade-offs influence prostate cancer risk? a review of population variation in testosterone levels and prostate cancer disparities.

    PubMed

    Alvarado, Louis Calistro

    2013-01-01

    An accumulation of evidence suggests that increased exposure to androgens is associated with prostate cancer risk. The unrestricted energy budget that is typical of Western diets represents a novel departure from the conditions in which men's steroid physiology evolved and is capable of supporting distinctly elevated testosterone levels. Although nutritional constraints likely underlie divergent patterns of testosterone secretion between Westernized and non-Western men, considerable variability exists in men's testosterone levels and prostate cancer rates within Westernized populations. Here, I use evolutionary life history theory as a framework to examine prostate cancer risk. Life history theory posits trade-offs between investment in early reproduction and long-term survival. One corollary of life history theory is the 'challenge hypothesis', which predicts that males augment testosterone levels in response to intrasexual competition occurring within reproductive contexts. Understanding men's evolved steroid physiology may contribute toward understanding susceptibility to prostate cancer. Among well-nourished populations of Westerners, men's testosterone levels already represent an outlier of cross-cultural variation. I hypothesize that Westernized men in aggressive social environments, characterized by intense male-male competition, will further augment testosterone production aggravating prostate cancer risk.

  20. Do evolutionary life-history trade-offs influence prostate cancer risk? a review of population variation in testosterone levels and prostate cancer disparities

    PubMed Central

    Alvarado, Louis Calistro

    2013-01-01

    An accumulation of evidence suggests that increased exposure to androgens is associated with prostate cancer risk. The unrestricted energy budget that is typical of Western diets represents a novel departure from the conditions in which men's steroid physiology evolved and is capable of supporting distinctly elevated testosterone levels. Although nutritional constraints likely underlie divergent patterns of testosterone secretion between Westernized and non-Western men, considerable variability exists in men's testosterone levels and prostate cancer rates within Westernized populations. Here, I use evolutionary life history theory as a framework to examine prostate cancer risk. Life history theory posits trade-offs between investment in early reproduction and long-term survival. One corollary of life history theory is the ‘challenge hypothesis’, which predicts that males augment testosterone levels in response to intrasexual competition occurring within reproductive contexts. Understanding men's evolved steroid physiology may contribute toward understanding susceptibility to prostate cancer. Among well-nourished populations of Westerners, men's testosterone levels already represent an outlier of cross-cultural variation. I hypothesize that Westernized men in aggressive social environments, characterized by intense male–male competition, will further augment testosterone production aggravating prostate cancer risk. PMID:23396824

  1. Endogenous Estradiol and Testosterone may Predispose toward Atherogenic Lipid Profile, but Higher Blood Level of Testosterone is Associated with Lower Number of Stenoses in the Coronary Arteries of Men with Coronary Disease

    PubMed Central

    Wranicz, Jerzy Krzysztof; Cygankiewicz, Iwona; Kula, Piotr; Walczak-Jedrzejowska, Renata; Slowikowska-Hilczer, Jolanta; Kula, Krzysztof

    2006-01-01

    Objectives: To assess the correlations between blood levels of sex steroid hormones and blood lipid profile or the degree of coronary artery stenosis in men with coronary artery disease (CAD). Methods: 111 men with stable CAD, aged 36-73 yrs, unselected for the coexisting clinical coronary risk factors were prospectively studied. Degree of coronary stenosis was assessed angiographically using different indices. Total cholesterol (T-Ch), high density lipoproteins cholesterol (HDL-Ch), low density lipoproteins cholesterol (LDL-Ch), triglicerydes (TG), testosterone, estradiol, dehydroepiandrosterone sulfate (DHEA-S), and sex hormone binding globulin (SHBG) were measured in the blood. Free testosterone index (FTI) was calculated. Results: A positive, significant correlations were found between blood concentrations of estradiol and T-Ch (r=0.29, p<0.01) or LDL-Ch (r=0.34, p<0.005) as well as between FTI and blood LDL-Ch (r=0.23, p<0.05). Blood level of estradiol negatively correlated with HDL-Ch/T-Ch ratio (r=-0.21, p<0.05). While blood levels of T-Ch correlated positively with 3 out of 5 applied here indices of coronary stenosis, blood LDL-Ch with two of them. In turn, blood level of testosterone negatively correlated with one index of coronary stenosis (r=-0.26, p<0.05). Conclusion: In men with CAD, plasma estradiol concentrations are predictive for T-Ch, LDL-Ch and HDL-Ch/TCh ratio, and FTI for LDL-Ch. Regression analyses indicated that while sex steroid hormones may predispose toward atherogenic lipid profile and are predictive for the number and degree of coronary artery stenosis, higher blood level of total testosterone was associated with the lower number of stenosis in the coronary arteries. Hence, endogenous testosterone may have beneficial effect on coronary arteries. PMID:23674975

  2. Peculiar observations in measuring testosterone in women treated with oral contraceptives supplemented with dehydroepiandrosterone (DHEA).

    PubMed

    Heijboer, Annemieke C; Zimmerman, Yvette; de Boer, Theo; Coelingh Bennink, Herjan; Blankenstein, Marinus A

    2014-03-20

    Total testosterone is considered to be decreased during the use of combined oral contraceptives. There is, however, considerable concern about the quality of testosterone assays, especially at low levels. We aimed to confirm testosterone levels measured by direct radioimmunoassay in a recent clinical trial with a state-of-the-art LC-MSMS method. Surplus specimens with known testosterone levels collected during the study (Clinical Trial Registration number ISRCTN06414473) were reanalyzed with an LC-MSMS method. This method was compared to another LC-MSMS method that had shown to concur excellently to a reference method. Follow-up experiments were designed to explain the results. In contrast to our expectation, LC-MSMS measurements did not corroborate the data obtained by radioimmunoassay. Subsequent experiments showed that this could be attributed to a strong dependency of the radioimmunoassay on SHBG. Testosterone results (n = 198) obtained by direct radioimmunoassay showed a negative correlation to SHBG levels (r = -0.676; p<0.001). By contrast, testosterone results obtained by LC-MSMS were not related to SHBG (r = 0.100; NS). In conclusion, our results indicate that total testosterone measurements during oral contraceptive use are unreliable when performed with assays sensitive to the SHBG concentration. The discrepancy with the literature can most likely be explained by the sensitivity of the immunoassay used to SHBG. Given the sharp increase in SHBG during the use of many oral contraceptives, total testosterone may not decrease, whereas its bioavailability, estimated by free testosterone levels, will be diminished. Studies aiming at restoration of testosterone homeostasis during oral contraception need to take this into account.

  3. Prospective Analysis on the Effect of Botanical Medicine (Tribulus terrestris) on Serum Testosterone Level and Semen Parameters in Males with Unexplained Infertility.

    PubMed

    Roaiah, Mohamed Farid; Elkhayat, Yasser Ibrahim; Saleh, Sameh Fayek GamalEl Din; Abd El Salam, Mohamed Ahmed

    2016-06-23

    We evaluated the role of Tribulus terrestris in males with unexplained infertility and its effect on serum testosterone and semen parameters. Thirty randomized male patients presenting to Andrology outpatient clinic complaining of idiopathic infertility were selected. They were given Tribulus terrestris (750 mg) in three divided doses for three months. The effect of Tribulus terrestris on serum testosterone (total and free) and luteinizing hormone (LH), as well as its impact on semen parameters in those patients, was studied. No statistically significant difference was observed in the levels of testosterone (total and free) and LH and semen parameters (sperm concentration or motility, or abnormal forms) before and after the treatment. In addition, no statistically significant correlations were observed between testosterone (free and total) and LH and semen parameters before and after the treatment. Tribulus terrestris was ineffective in the treatment of idiopathic infertility.

  4. The interaction of serum testosterone levels and androgen receptor CAG repeat polymorphism on the risk of erectile dysfunction in aging Taiwanese men.

    PubMed

    Liu, C C; Lee, Y C; Tsai, V F S; Cheng, K H; Wu, W J; Bao, B Y; Huang, C N; Yeh, H C; Tsai, C C; Wang, C J; Huang, S P

    2015-09-01

    Testosterone has been found to play important roles in men's sexual function. However, the effects of testosterone can be modulated by androgen receptor (AR) CAG repeat polymorphism. It could also contribute to the risk of erectile dysfunction (ED). The aim of this study is to evaluate the interaction of serum testosterone levels and AR CAG repeat polymorphism on the risk of ED in aging Taiwanese men. This cross-sectional data of Taiwanese men older than 40 years were collected from a free health screening held between August 2010 and August 2011 in Kaohsiung city, Taiwan. All participants completed a health questionnaires included five-item version of the International Index of Erectile Function (IIEF-5) and the International Prostate Symptoms Score, received a detailed physical examination and provided 20 cm3 whole blood samples for biochemical and genetic evaluation. The IIEF-5 was used to evaluate ED. Serum albumin, total testosterone (TT), and sex hormone-binding globulin levels were measured. Free testosterone level was calculated. AR gene CAG repeat polymorphism was determined by direct sequencing. Finally, 478 men with the mean age of 55.7 ± 4.8 years were included. When TT levels were above 330 ng/dL, the effect of testosterone level on erectile function seemed to reach a plateau and a significantly negative correlation between AR CAG repeat length and the score of IIEF-5 was found (r = -0.119, p = 0.034). After adjusting for other covariates, the longer AR CAG repeat length was still an independent risk factor for ED in subjects with TT above 330 ng/dL (p = 0.006), but not in TT of 330 ng/dL or below. In conclusion, both serum testosterone levels and AR CAG repeat polymorphism can influence erectile function concomitantly. In subjects with normal TT concentration, those with longer AR CAG repeat lengths have a higher risk of developing ED.

  5. Scent marking, dominance and serum testosterone levels in male domestic rabbits.

    PubMed

    Arteaga, Lourdes; Bautista, Amando; Martínez-Gómez, Margarita; Nicolás, Leticia; Hudson, Robyn

    2008-06-09

    The European rabbit, both in its wild and domesticated forms, has been a pioneer species in the study of mammalian chemical communication, and illustrates well the difficulty of understanding the functional significance of these often complex signals. Here we investigate the performance of one of the rabbit's most conspicuous chemical signaling behaviors, chin marking (chinning), and the hypothesis that this expresses social dominance. In tests of 21 chinchilla-strain sexually mature males we predicted 1) that animals would show marked and stable individual differences in the frequency of chinning, 2) that these differences would correlate with behaviors associated with dominance such as intrasexual mounting, and 3) that individual differences in the frequency of chinning and dominance-related behaviors would correlate with individual differences in a commonly used physiological indicator of dominance, concentration of serum testosterone. Supporting these predictions and consistent with previous reports, animals showed large and stable individual differences in the frequency of chinning which correlated with the behavioral indicators of dominance and less strongly, with serum testosterone. As our animals had been kept in single cages and without direct contact with other males since weaning, these findings raise the question as to how and when during development such differences among individuals arise. We are currently investigating the possible relation between pups' intrauterine position, postnatal competition among littermates for milk and thermally advantageous positions in the litter huddle, and later differences in indicators of dominance such as those reported here.

  6. [Testosterone therapy].

    PubMed

    Diemer, T; Hauptmann, A; Wagenlehner, F M E

    2016-04-01

    Hormone replacement therapy with testosterone has become well-established over the course of time. The initial substantial concerns with respect to complications and potential adverse events, particularly in older patients, were proven to be unfounded over time. Testosterone therapy has therefore gradually become a regular treatment modality in urological practice. It has also been shown to represent a valuable tool as supportive treatment for patients with erectile dysfunction and hypogonadism. A variety of testosterone preparations are available for treatment. Recent pharmaceutical developments have greatly improved the practicability and ease of administration for patients. Several guidelines have been developed that provide clearly formulated standards and instructions for indications, contraindications, application, risk factors and monitoring of testosterone therapy. Adverse events affecting the cardiovascular system and especially diseases of the prostate gland are of great importance, thus making the urologist the primary partner in the treatment of patients with testosterone deficiency.

  7. Is there a relationship between the performance in a chronometric mental-rotations test and salivary testosterone and estradiol levels in children aged 9-14 years?

    PubMed

    Quaiser-Pohl, Claudia; Jansen, Petra; Lehmann, Jennifer; Kudielka, Brigitte M

    2016-01-01

    The consistent gender differences favoring males in some spatial abilities like mental rotation have raised the question of whether testosterone or other gonadal hormones contribute to these differences--especially because such gender differences seem to appear mainly from the age of puberty on. Studies generally suggest that spatial ability is facilitated by moderately high testosterone levels (i.e., levels that are relatively high for females and relatively low for males). However, the role of sex steroids for mental-rotation performance of (pre-) pubertal children has not been the focus of research, yet. In our study, the relationships between different aspects of mental-rotation performance (accuracy, reaction time, rotation speed) and salivary testosterone and estradiol levels were investigated. Subjects were 109 children (51 boys and 58 girls) aged between 9 and 14 years (M = 11.41, SD = 1.74). They performed a chronometric mental-rotations test, in which the stimuli consisted of three-dimensional drawings of Shepard and Metzler cube figures. In addition, saliva samples were gathered for the analysis of free testosterone and estradiol levels. Results showed a significant gender difference in reaction time and rotational speed in favor of boys, and a significant age, but no gender difference in testosterone and estradiol levels. We found no significant relationships between hormonal levels and any measure of mental-rotation performance.

  8. Bio-availability of iron from spinach (Spanicia oleracea) cultivated in soil fortified with graded levels of iron.

    PubMed

    Reddy, N S; Malewar, V G

    1992-10-01

    In vitro availability of iron along with ascorbic acid, oxalic acid and phosphorus contents of two varieties of spinach (Pusa Jyoti and Allgreen) cultivated in soil with different levels of added iron was determined. Addition of graded levels of iron to soil markedly increased the total iron and phosphorus contents and significantly decreased the bio-availability of iron, ascorbic acid and oxalic acid contents of spinach. Ascorbic acid and oxalic acid contents markedly exerted a positive influence while phosphorus exerted a negative influence on the bio-availability of iron.

  9. An Overview of Testosterone Therapy.

    PubMed

    Lee, O Danny; Tillman, Ken

    2016-01-01

    Millions of men, as a result of the natural aging process, injury, illness, and medical therapies, experience a decline in testosterone levels that necessitate a need for testosterone supplementation therapy (TST). The signs and symptoms of testosterone decline may occur gradually, and low testosterone levels may be misdiagnosed as other medical conditions. Over the past two decades, there has been an increase in testing of testosterone levels and the use of TST. With so many men now on TST, it is essential for health care professionals to know the signs and symptoms, the causes of testosterone decline, how testosterone deficiency is diagnosed, what pathological changes are associated with testosterone decline, and the benefits and risks of TST. In addition, health care providers need to be aware of the various forms of testosterone available as well as the advantages and disadvantages of each. This article provides a brief overview of testosterone deficiency, TST treatment options and guidelines, and the risks and benefits associated with of TST.

  10. Diet exposure to technical hexabromocyclododecane (HBCD) affects testes and circulating testosterone and thyroxine levels in American kestrels (Falco sparverius).

    PubMed

    Marteinson, Sarah C; Kimmins, Sarah; Letcher, Robert J; Palace, Vince P; Bird, David M; Ritchie, Ian J; Fernie, Kim J

    2011-11-01

    Hexabromocyclododecane (HBCD) is a high-production-volume, brominated flame-retardant that is used in items such as polystyrene foams. HBCD has been detected in the environment, wildlife tissues and in humans globally with some of the highest recorded levels in predatory birds. This study examined the effects of exposure to environmentally relevant levels of HBCD on the reproductive physiology of captive male American kestrels (Falco sparverius), a predatory bird. Two sets of males were used: one group not housed with females (unpaired: nc=12, nHBCD=10) and the second group housed with females (breeding: nc=10, nHBCD=20). All treatment birds were exposed to 0.51 μg HBCD/g kestrel/day technical HBCD, and controls to safflower oil only, injected into their food during seasonal testicular development. Unpaired males were exposed for 3 weeks and euthanized for testicular analysis. Breeding males were exposed for 3 weeks prior to pairing and throughout the courtship period. The HBCD-exposed unpaired males had heavier testes (p≤0.017) and a trend towards more seminiferous tubules containing elongated spermatids (p=0.052). There was also a moderate increase in plasma testosterone concentrations (p=0.056) compared to controls. In breeding males, testosterone levels increased during courtship to culminate in higher levels than controls by the time the first egg was laid (p=0.010) and circulating free and total T4 was reduced throughout. The number of sperm cells reaching the perivitelline layer of the first egg for breeding males did not differ between the two groups. This study is the first report that HBCD exposure at environmentally relevant levels alters reproductive physiology in male birds and suggests that birds may be more sensitive to HBCD than mammals.

  11. Controversies in testosterone replacement therapy: testosterone and cardiovascular disease.

    PubMed

    Hwang, Kathleen; Miner, Martin

    2015-01-01

    The role of testosterone in the cardiovascular (CV) health of men is controversial. Data suggest that both the condition and treatment of clinical hypogonadism is associated with decreased CV mortality; however, two recent studies suggest that hypogonadal subjects treated with testosterone replacement therapy have a higher incidence of new CV events. There has been increased media attention concerning the risk of CV disease in men treated with testosterone. Until date, there are no long-term prospective studies to determine safety. Literature spanning over the past 30 years has suggested that not only is there a possible increased CV risk in men with low levels of testosterone, but the benefits from testosterone therapy may even lower this risk. We review here the recent studies that have garnered such intense scrutiny. This article is intended as a thorough review of testosterone levels and CV risk, providing the clinician with the facts needed to make informed clinical decisions in managing patients with clinical hypogonadism.

  12. Testosterone Test

    MedlinePlus

    ... diagnose several conditions in men, women, girls, and boys. Testosterone is the main sex hormone in men, ... such as: Delayed or precocious (early) puberty in boys Decreased sex drive in men and women Erectile ...

  13. Maternal corticosterone but not testosterone level is associated with the ratio of second-to-fourth digit length (2D:4D) in field vole offspring (Microtus agrestis).

    PubMed

    Lilley, Thomas; Laaksonen, Toni; Huitu, Otso; Helle, Samuli

    2010-03-30

    The steroid environment encountered by a foetus can strongly affect its post-natal physiology and behaviour. It has been proposed that steroid concentrations experienced in utero could be estimated from adults by measuring their second-to-fourth digit length ratio (2D:4D). However, there is still little direct evidence that intra-uterine steroid levels affect individual 2D:4D. We examined whether maternal pre-pregnancy testosterone and corticosterone levels (as estimates of intra-uterine testosterone and corticosterone exposure) affected the 2D:4D of pups in non-domesticated field voles (Microtus agrestis), measured by X-rays at the age of weaning (21 days). Furthermore, for the first time in a non-human species, we studied whether testosterone and corticosterone levels correlated with 2D:4D in adult females. We found that the maternal pre-pregnancy level of testosterone was not associated with offspring 2D:4D in either the left or the right paw. Instead, maternal pre-pregnancy corticosterone level was positively correlated with offspring 2D:4D in the right paw, but unrelated to 2D:4D in the left paw. In addition, the 2D:4D of adult females was not associated with either their circulating testosterone or corticosterone levels. Our results suggest that in field voles maternally administered testosterone is not a major determinant of offspring 2D:4D, whereas maternal stress appears to account for some of the variation in the 2D:4D of their offspring.

  14. 1H NMR Metabolomics: A New Molecular Level Tool for Assessment of Organic Contaminant Bioavailability to Earthworms in Soil

    NASA Astrophysics Data System (ADS)

    McKelvie, J. R.; Wolfe, D. M.; Celejewski, M. A.; Simpson, A. J.; Simpson, M. J.

    2009-05-01

    extractable using cyclodextrin. Hence, while cyclodextrin extraction may serve as a good proxy for microbial bioavailability, our results suggest that it may not serve as a good proxy for earthworm bioavailability. 1H NMR metabolomics therefore offers considerable promise as a novel, molecular-level method to directly monitor earthworm bioavailability of potentially toxic and persistent compounds in the environment.

  15. Validation of a radioimmunoassay for measuring testosterone concentrations in plasma samples of the subterranean rodent Ctenomys talarum: outstandingly elevated levels in the wild and the effect of captivity.

    PubMed

    Vera, Federico; Zenuto, Roxana Rita; Antenucci, Carlos Daniel; Busso, Juan Manuel; Marín, Raúl Héctor

    2011-11-01

    We validated the Coat-a-Count radioimmunoassay (RIA) kit for measuring testosterone in plasma samples of the subterranean rodent Ctenomys talarum and evaluated testosterone levels in free-living and captive individuals. The performance of the assay was evaluated by the assessment of parallelism, accuracy and precision. Moreover, the high specificity of the assay antibody was confirmed by high-pressure liquid chromatography with ultraviolet detector, followed by electrospray ionization tandem mass spectrometry. Results indicated that plasma samples have to be treated with heat and diluted before the RIA for the optimization of the assay. Plasma testosterone concentrations in free-living animals were outstandingly elevated (up to 329 ng/mL), which are among the highest ever reported for mammals. On the other hand, captivity produced a 14-fold decrease in plasma testosterone concentrations, emphasizing that very significant changes in the endocrine milieu may occur in wild animals kept under laboratory conditions. Our results place tuco-tucos as an interesting model for the study of androgen regulation in mammals, suggesting that target tissues may have low sensitivity to the testosterone signal and agree with a scenario of elevated levels of sex hormone-binding globulin in plasma.

  16. Additive benefit of higher testosterone levels and vitamin D plus calcium supplementation in regard to fall risk reduction among older men and women

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both testosterone and vitamin D levels affect muscle and thus may also affect risk of falling. The aim of this study was to investigate the association between sex hormone levels and the risk of falling in older men and women. 199 men and 246 women age 65 or older living at home followed for 3 years...

  17. Spermatogenesis and plasma testosterone levels in Western Australian burrowing desert frogs, Cyclorana platycephala, Cyclorana maini, and Neobatrachus sutor, during aestivation.

    PubMed

    Shalan, A G; Bradshaw, S D; Withers, P C; Thompson, G; Bayomy, M F F; Bradshaw, F J; Stewart, T

    2004-03-01

    Changes in testis size, histological status, and plasma levels of testosterone were monitored for males of three species of Western Australian desert frogs, Cyclorana maini, Cyclorana platycephala, and Neobatrachus sutor during aestivation. The frogs were induced to burrow and form cocoons soon after their capture and then disinterred at intervals in order to monitor changes in reproductive activity of the testes. All stages of spermatogenesis were evident in active frogs, which were collected a few days following rain from breeding choruses. Relative testis mass declined gradually in all species during the first 7 months of aestivation and then increased significantly at 16-19 months in the two species for which extended data were available (C. maini and N. sutor). A decrease in the number of sperm bundles 2-4 months after cocooning was associated with an initial increase in the number of free spermatazoa in all three species, which then returned to the levels seen in active animals after 7 months. Increases in the number of primary and secondary spermatogonia were most evident in C. platycephala after 4-7 months of aestivation, but early stages of spermatocytogenesis were evident in all species after 7 months of aestivation, especially in individuals that contained neither sperm bundles nor mature spermatazoa. Changes in plasma testosterone levels correlated significantly with variations in the diameter of the seminiferous tubules and the GSI, suggesting that this hormone plays a major role in controlling testicular recrudescence in aestivating, cocooned, desert frogs. Data from this study show that, in the absence of any external cues, testicular recrudescence is evident after approximately one year of aestivation in desert frogs which prepares them to breed again, once rain falls.

  18. The changes of serum testosterone level and hepatic microsome enzyme activity of crucian carp (Carassius carassius) exposed to a sublethal dosage of pentachlorophenol.

    PubMed

    Zhang, Min; Yin, Daqiang; Kong, Fanxiang

    2008-10-01

    Pentachlorophenol (PCP), which was reported to be a typical persistent organic pollutant and environmental endocrine disruptor, may cause threat to aquatic species. In this study, serum testosterone concentration, activity of liver microsome ethoxyresorufin O-deethylase (EROD) and glutathione S-transferases (GST) of crucian carp (Carassius carassius) exposed to PCP for 7 and 15 d, respectively, were examined. The results showed that testosterone concentration was induced remarkably after 7 d (P<0.05), and the testosterone concentrations in 15 d treatment crucian carp were higher than those in 7 d treatment. It was found that there were significant effects on activities of EROD and GST after crucian carp were exposed to PCP for 7 and 15 d (P<0.05), compared to the controls. EROD and GST activities increased with increase in PCP concentration and also with increase in time on exposure. The results indicated that serum testosterone, EROD and GST were sensitive endpoints to PCP. PCP may have endocrine disrupting activities and may affect the reproductive success of this species. It is possible that the changes of hepatic microsome enzyme activities may result in alterations of serum testosterone levels in crucian carp.

  19. Seasonal and inter-individual variation in testosterone levels in badgers Meles meles: evidence for the existence of two endocrinological phenotypes.

    PubMed

    Buesching, Christina Dagmar; Heistermann, Michael; Macdonald, David W

    2009-09-01

    Elevated testosterone levels can lower condition and increase parasites. We analysed testosterone in 84 blood samples of wild European badgers Meles meles collected at regular intervals (winter = mating season; spring = end of mating season; summer = minor mating peak; autumn = reproductive quiescence), and related variation to body condition, subcaudal gland secretion, parasite burden, and bite wounding. All males showed elevated levels in winter and low levels in autumn. In neither season did testosterone correlate with fitness-related parameters. However, two different endocrinological phenotypes existed in spring and summer. Whilst some males lowered their testosterone to levels comparable to autumnal quiescence (Type 1), others maintained elevated levels comparable to those during winter (Type 2). In spring and summer high levels were correlated with lower body condition and increased parasite burden, and Type 2 males tended to suffer higher mortality rates than Type 1. No animals older than 6 years adopted phenotype 2, indicating that males either switch phenotypes with age or that Type 2 results in lower life expectancy, evidencing the costs of male reproduction in badgers.

  20. Bioavailability of caesium-137 from chernozem soils with high and low levels of radioactive contamination

    NASA Astrophysics Data System (ADS)

    Paramonova, Tatiana; Shamshurina, Eugenia; Machaeva, Ekaterina; Belyaev, Vladimir

    2014-05-01

    Bioavailability of Cs-137 in "soil-plant" system of radioactively contaminated terrestrial ecosystems is the most important factor in the understanding of ecological situation. There are many factors affecting the features of Cs-137 biogeochemical cycle: period since an accident, type and intensity of radioactive fallout, general properties of landscape and the specifics of soil and plant covers, etc. In order to evaluate the importance of soil contamination level for the process of Cs-137 translocation from soil to plant the research in forest-steppe areas of Russia with similar natural properties, but contrasting high (Tula region) and low (Kursk region) levels of radioactive Chernobyl fallout (about 25 years after accident) was conducted. Soil cover of both sites is presented by chernozems with bulk density 1.1-1.2 g/cm3, 6-7% humus and neutral pH 6.5-7.2; plant cover under investigation consist of dry and wet meadows with bioproductivity 1.6-2.5 kg/m2 and 85-90% of biomass concentrated underground, that is typical for Russian forest-steppe landscapes. At the same time levels of soil regional contamination with Cs-137 differ by an order - 620-710 Bq/kg (210-250 kBq/m2) in Tula region and 30-55 Bq/kg (10-20 kBq/m2) in Kursk region. At a higher level of soil radioactive contamination specific activity of Cs-137 in vegetation of meadows is noticeably increased (103-160 Bq/kg in Tula region versus 12-14 Bq/kg in Kursk region) with correlation coefficient r 0.87. Increasing of Cs-137 in the underground parts of plants plays a decisive role in this process, while the specific radionuclide's activity in the aboveground parts of different sites is almost invariant (and ubiquitously roots contain 2-5 times more Cs-137 than shoots). The values of transfer factors for Cs-137 (the ratio of the specific Cs-137 activities in the plant tissue and in the soil) at various levels of soil radioactive contamination vary within a relatively narrow range 0.1-0.4, that confirms the

  1. Facial Width-To-Height Ratio (fWHR) Is Not Associated with Adolescent Testosterone Levels

    PubMed Central

    Hodges-Simeon, Carolyn R.; Hanson Sobraske, Katherine N.; Samore, Theodore; Gurven, Michael; Gaulin, Steven J. C.

    2016-01-01

    Facial width-to-height ratio (fWHR) has been proposed as a sexually dimorphic signal in humans that develops under the influence of pubertal testosterone (T); however, no studies have examined the association between fWHR and T during the phase in which facial growth is canalized—adolescence. In a sample of adolescent Tsimane males, we evaluate the relationship between T, known T-derived traits (i.e. strength and voice pitch), and craniofacial measurements. If fWHR variation derives from T’s effect on craniofacial growth during adolescence, several predictions should be supported: 1) fWHR should increase with age as T increases, 2) fWHR should reflect adolescent T (rather than adult T per se), 3) fWHR should exhibit velocity changes during adolescence in parallel with the pubertal spurt in T, 4) fWHR should correlate with T after controlling for age and other potential confounds, and 5) fWHR should show strong associations with other T-derived traits. Only prediction 4 was observed. Additionally, we examined three alternative facial masculinity ratios: facial width/lower face height, cheekbone prominence, and facial width/full face height. In contrast to fWHR, all three alternative measures show a strong age-related trend and are associated with both T and T-dependent traits. Overall, our results question the status of fWHR as a sexually-selected signal of pubertal T and T-linked traits. PMID:27078636

  2. Role of free testosterone levels in patients with metastatic castration-resistant prostate cancer receiving second-line therapy

    PubMed Central

    von Klot, Christoph A.; Kuczyk, Markus A.; Boeker, Alena; Reuter, Christoph; Imkamp, Florian; Herrmann, Thomas R.W.; Tezval, Hossein; Kramer, Mario W.; Perner, Sven; Merseburger, Axel S.

    2017-01-01

    A range of new treatment options has recently become available for patients with advanced metastatic castration-resistant prostate cancer (mCRPC). Androgen deprivation therapy (ADT) with luteinizing hormone-releasing hormone is continued when performing chemotherapy or androgen deprivation with new second-generation therapeutic agents such as enzalutamide or abiraterone acetate. Despite the fact that free testosterone (FT) is the biologically active form, it is common practice that androgen suppression is monitored via total testosterone levels only. The aim of the present study was to evaluate the role of FT as a prognostic biomarker for cancer-specific survival (CSS) and its feasibility as an ADT monitoring biomarker in patients with mCRPC for the first time. The requirement for continued ADT in mCRPC patients is discussed within the basis of the current literature. A total of 34 patients with continuous measurements of FT levels and mCRPC status underwent therapy with docetaxel, abiraterone acetate, enzalutamide, cabozantinib, carboplatin or cabazitaxel. Data were obtained from the Departments of Urology and Urological Oncology, Hannover Medical School (Hannover, Germany) between March 2009 and April 2014. A cutoff point of 0.5 pg/ml was used to discriminate between patients according to FT levels. Statistical evaluation of CSS was performed by applying Kaplan Meier survival estimates, multivariate Cox regression analyses and log-rank tests. The median age of all 34 patients was 72 years (range, 51–86 years). The mean follow-up interval was 16.1 months (range, 0.7–55.6 months). Despite the fact that all patients were undergoing androgen deprivation, the mean serum FT levels for each patient varied; the mean FT concentration in the cohort was 0.328 pg/ml, ranging from 0.01–9.1 pg/ml. A notable difference with regard to CSS was observed for patients with regard to serum FT concentration; CSS was significantly longer for patients with a serum FT level below

  3. Effect of red maca (Lepidium meyenii) on prostate zinc levels in rats with testosterone-induced prostatic hyperplasia.

    PubMed

    Gonzales, C; Leiva-Revilla, J; Rubio, J; Gasco, M; Gonzales, G F

    2012-05-01

    Lepidium meyenii (maca) is a plant that grows exclusively above 4000 m in the Peruvian central Andes. Red maca (RM) extract significantly reduced prostate size in rats with benign prostatic hyperplasia (BPH) induced by testosterone enanthate (TE). Zinc is an important regulator of prostate function. This study aimed to determine the effect of RM on prostate zinc levels in rats with BPH induced by TE. Also, the study attempted to determine the best marker for the effect of RM on sex accessory glands. Rats treated with RM extract from day 1 to day 14 reversed the effect of TE administration on prostate weight and zinc levels. However, RM administered from day 7 to day 14 did not reduce the effect of TE on all studied variables. Finasteride (FN) reduced prostate, seminal vesicle and preputial gland weights in rats treated with TE. Although RM and FN reduced prostate zinc levels, the greatest effect was observed in TE-treated rats with RM from day 1 to day 14. In addition, prostate weight and zinc levels showed the higher diagnosis values than preputial and seminal vesicle weights. In conclusion, RM administered from day 1 to day 14 reduced prostate size and zinc levels in rats where prostatic hyperplasia was induced with TE. Also, this experimental model could be used as accurately assay to determine the effect of maca obtained under different conditions and/or the effect of different products based on maca.

  4. Effect of voluntary exercise on the expression of IGF-I and androgen receptor in three rat skeletal muscles and on serum IGF-I and testosterone levels.

    PubMed

    Matsakas, A; Nikolaidis, M G; Kokalas, N; Mougios, V; Diel, P

    2004-10-01

    The effects of anabolic agents and training on skeletal muscle are believed to be mediated by a variety of growth and transcription factors. Among these regulatory proteins, insulin-like growth factor-I (IGF-I) and androgen receptor (AR) play a crucial role. The purpose of this study was to investigate the effects of wheel running on IGF-I and AR mRNA expression in three distinct rat skeletal muscles (i.e., gastrocnemius, vastus lateralis, and soleus), as well as on the serum levels of IGF-I and testosterone. Twenty male Wistar rats were housed in cages with free access to running wheels for 12 weeks, while nine rats served as controls. Analysis of the mRNA expression of IGF-I and AR using real time RT-PCR revealed no significant differences between the trained and untrained rats in any of the muscles studied. Enzyme immunoassay showed significantly lower serum levels of IGF-I and testosterone in the trained compared to the untrained animals. These results suggest that chronic exercise in wheels does not affect IGF-I and AR mRNA levels in rat skeletal muscle, while decreasing the circulating levels of two anabolic factors, i.e., IGF-I and testosterone. It is concluded that IGF-I, AR and testosterone seem to play a marginal role during the adaptation process of rat skeletal muscle to long-term wheel running.

  5. The effect of testosterone replacement therapy on prostate-specific antigen (PSA) levels in men being treated for hypogonadism: a systematic review and meta-analysis.

    PubMed

    Kang, De-Ying; Li, Hong-Jun

    2015-01-01

    Testosterone replacement therapy is used for the treatment of age-related male hypogonadism, and prostate-specific antigen (PSA) is a primary screening tool for prostate cancer. The systematic review and meta-analysis aimed to determine the effect of testosterone replacement therapy on PSA levels.Medline, Cochrane Library, EMBASE, and Google Scholar databases were searched until February 28, 2014, and inclusion criteria were as follows: randomized controlled trial; intervention group received testosterone/androgen replacement therapy; control group did not receive treatment; and no history of prostate cancer. The primary outcome was change of PSA level between before and after treatment. Secondary outcomes were elevated PSA level after treatment, and the number of patients who developed prostate cancer.After initially identifying 511 articles, 15 studies with a total of 739 patients that received testosterone replacement and 385 controls were included. The duration of treatment ranged from 3 to 12 months. Patients treated with testosterone tended to have higher PSA levels, and thus a greater change than those that received control treatments (difference in means of PSA levels = 0.154, 95% confidence interval [CI] 0.069 to 0.238, P < 0.001). The difference in means of PSA levels were significant higher for patients that received testosterone intramuscularly (IM) than controls (difference in means of PSA levels = 0.271, 95% CI 0.117-0.425, P = 0.001). Elevated PSA levels after treatment were similar between patients that received treatment and controls (odds ratio [OR] = 1.02, 95% CI 0.48-2.20, P = 0.953). Only 3 studies provided data with respect to the development of prostate cancer, and rates were similar between those that received treatment and controls.Testosterone replacement therapy does not increase PSA levels in men being treated for hypogonadism, except when it is given IM and even the increase with IM administration is minimal.

  6. Testosterone replacement therapy and prostate health.

    PubMed

    Polackwich, A Scott; Ostrowski, Kevin A; Hedges, Jason C

    2012-12-01

    There is an emerging evolution in the understanding of the relationship between the prostate and testosterone. It has long been generally believed that with testosterone replacement therapy (TRT), increasing serum testosterone levels led to prostatic growth and worsening of voiding dysfunction and associated complications. A new theory, the Saturation Model of Testosterone and its effect on the Prostate has gained attention. This theory suggests that the prostate's response to increasing levels of serum testosterone reaches a limit beyond which there is minimal effect. This model predicts that testosterone replacement therapy occurs above this saturation point, and replacing testosterone to eugonadal levels should not worsen prostate related benign disease. We evaluated the recent published data, with an emphasis on clinical studies done within the last 3 years, for the effects of testosterone supplementation on benign prostatic disease.

  7. Differences in testosterone, androstenone, and skatole levels in plasma and fat between pubertal purebred Duroc and Landrace boars in response to human chorionic gonadotrophin stimulation.

    PubMed

    Oskam, I C; Lervik, S; Tajet, H; Dahl, E; Ropstad, E; Andresen, Ø

    2010-10-01

    The concentrations of the boar taint compounds androstenone and skatole in plasma and fat, together with those of testosterone in plasma, were investigated in pubertal purebred Duroc and Landrace boars following stimulation with human chorionic gonadotrophin (hCG). Higher initial levels of androstenone and testosterone were found in Duroc than Landrace boars. Duroc boars, which were approximately ten days older than the Landrace boars, also showed a more advanced stage of spermatogenesis than Landrace boars. While Landrace boars had the highest skatole levels. Following stimulation with hCG the relative increases in testosterone, androstenone, and skatole concentrations were highest in Landrace boars. The level of androstenone in fat three days after hCG stimulation exceeded 1 microg/g fat in all stimulated boars. The decreases in plasma levels of androstenone and testosterone on Days 2 and 3 after hCG stimulation were more pronounced in Landrace than Duroc boars. However, unlike the plasma androstenone and testosterone levels, the plasma concentrations of skatole did not decrease on Days 2 and 3 following stimulation, but remained elevated on Day 3. These results indicate that the lower levels of testicular steroids in Landrace boars compared with Duroc boars was not due to a lower production capacity, but more likely to a faster disappearance of steroids in Landrace boars. In the present study, age, live weight, and testicular development did not significantly contribute to the variation in fat androstenone. The present data and previous reports on candidate genes related to androstenone biosynthesis and metabolism suggests that future selection against factors associated with boar taint remains a possible solution for the problem of boar taint in the swine industry.

  8. Pilot Study on the Effect of Botanical Medicine (Tribulus terrestris) on Serum Testosterone Level and Erectile Function in Aging Males With Partial Androgen Deficiency (PADAM).

    PubMed

    Roaiah, Mohamed Farid; El Khayat, Yasser Ibrahim; GamalEl Din, Sameh Fayek; Abd El Salam, Mohamed Ahmed

    2016-05-18

    This study was conducted on 30 consecutive male patients presenting to Kasr-Al Ainy Andrology outpatient clinic complaining of manifestations of partial androgen deficiency in aging males (PADAM). In this study (750 mg/day) of Tribulus terrestris in 3 divided doses, each of 250 mg, as an endogenous testosterone enhancer had been tried for a duration of 3 months and the evaluation of its effect had been monitored for each patient concerning its effect on serum testosterone (total and free) and luteinizing hormone (LH), as well as its impact on erectile function, which was evaluated by the International Index of Erectile Function-5 (IIEF-5) questionnaire for those patients. Results showed a statistically significant difference in the level of testosterone (total and free) and IIEF-5, but no statistically significant difference in the level of LH before and after treatment. Also, the study showed statistically significant correlation between testosterone (total and free) and IIEF-5, but no statistically significant correlation between the level of LH and the IIEF-5 before and after treatment.

  9. Fetal Testosterone, Socio-Emotional Engagement and Language Development

    ERIC Educational Resources Information Center

    Farrant, Brad M.; Mattes, Eugen; Keelan, Jeff A.; Hickey, Martha; Whitehouse, Andrew J. O.

    2013-01-01

    The present study investigated the relations among fetal testosterone, child socio-emotional engagement and language development in a sample of 467 children (235 boys) from the Western Australian Pregnancy Cohort (Raine) Study. Bioavailable testosterone concentration measured in umbilical cord blood taken at birth was found to be significantly…

  10. Testosterone and Men's Marriages.

    ERIC Educational Resources Information Center

    Booth, Alan; Dabbs, James M., Jr.

    1993-01-01

    Among 4,462 former servicemen surveyed, testosterone levels were positively related to not marrying and marital instability, and negatively related to every aspect of marital quality examined. Findings are analyzed in relation to three sociological theories of marital success based on socioeconomic status (educational attainment, income, and…

  11. Polymorphism in the Alternative Donor Site of the Cryptic Exon of LHCGR: Functional Consequences and Associations with Testosterone Level

    PubMed Central

    Liu, Wei; Han, Bing; Zhu, Wenjiao; Cheng, Tong; Fan, Mengxia; Wu, Jiajun; Yang, Ying; Zhu, Hui; Si, Jiqiang; Lyu, Qifeng; Chai, Weiran; Zhao, Shuangxia; Song, Huaidong; Kuang, Yanping; Qiao, Jie

    2017-01-01

    Selective splicing is a feature of luteinizing hormone receptor (LHCGR). A cryptic exon (LHCGR-exon 6A) was found to be derived from alternative splicing in intron 6 of the LHCGR gene, which including two transcripts LHCGR-exon 6A-long and LHCGR-exon 6A-short. We addressed the functional consequences of SNP rs68073206, located at the +5 position of an alternative 5′ splice donor site, and observed its association with male infertility in the subjects with azoospermia, oligoasthenozoospermia and normozoospermia. The translation product of splicing variant LHCGR-exon 6A was expressed in the cytoplasm and exhibited no affinity with [125I]-hCG. No dominant negative effect was observed in cells co-expressed with LHCGR-exon 6A and wild-type LHCGR. The long transcript (LHCGR-exon 6A-long) was significantly elevated in the granulosa cells with G/G genotypes, which could be reproduced in vitro by mini-gene construct transfection. Genotyping analysis showed no association between rs68073206 and male infertility. However, this polymorphism was significantly associated with testosterone levels in normozoospermic subjects (n = 210). In conclusion, SNP rs68073206 in the splicing site of the cryptic exon 6A of the LHCGR gene affect the splicing pattern in the gene, which may play a role in the modulation of the LHCGR sensitivity in the gonads. PMID:28367994

  12. The Level of Testosterone, Vitamin D, and Irregular Menstruation More Important than Omega-3 in Non-Symptomatic Women Will Define the Fate of Multiple Scleroses in Future.

    PubMed

    Tavakol, Shima; Shakibapour, Sahar; Bidgoli, Sepideh Arbabi

    2016-12-13

    Multiple sclerosis is one of the most salient degenerative disorders of CNS with dysregulated immune process that resulted in axonal damage and demyelination. In the present investigation, the serum level of testosterone was assessed in women who were struggling with multiple sclerosis (MS). Also, the level of omega-3, vitamin D, and the irregular menstruation in women 5 years before the onset MS symptoms were surveyed. Although the levels of omega-3 and vitamin D in women MS patients were non-significant and significantly less than the healthy ones, they were significantly less in the whole population of MS patients. However, the MS patients more experienced more irregular menstruation some years before the onset of MS with the low level of testosterone. Based on the presented findings, it might be said that the vitamin D intake has significant protective role in women and men MS patients unlike the omega-3 that had significant protective role just in men. However, vitamin D metabolism encoding genes of CYP27B1 and CYP24A1 and predicting MS risk gene of HLA-DRB1*15:01 define its fate as well. Besides, vitamin D intake, through the proliferation decrement of pro-inflammatory cells, decreases of pro-inflammatory markers (IL-6, TNF-α, INF-γ) and auto-immune pathways have potential role in recovery of irregular menstruation in women with the low level of testosterone as a red warning factor of MS development. The low level of testosterone and vitamin D consumption increase the neural damage and pro-inflammatory pathways in MS patients, and the difference among the investigations is related to the long-standing history of MS that influences severity of damage to the neural cells and biomolecules and complicate its recovery.

  13. Former Abusers of Anabolic Androgenic Steroids Exhibit Decreased Testosterone Levels and Hypogonadal Symptoms Years after Cessation: A Case-Control Study

    PubMed Central

    Selmer, Christian; Østergren, Peter Busch; Pedersen, Karen Boje; Schou, Morten; Gustafsson, Finn; Faber, Jens; Juul, Anders; Kistorp, Caroline

    2016-01-01

    Aims Abuse of anabolic androgenic steroids (AAS) is highly prevalent among male recreational athletes. The objective of this study was to investigate the impact of AAS abuse on reproductive hormone levels and symptoms suggestive of hypogonadism in current and former AAS abusers. Methods This study had a cross-sectional case-control design and involved 37 current AAS abusers, 33 former AAS abusers (mean (95%CI) elapsed duration since AAS cessation: 2.5 (1.7; 3.7) years) and 30 healthy control participants. All participants were aged 18–50 years and were involved in recreational strength training. Reproductive hormones (FSH, LH, testosterone, inhibin B and anti-Müllerian hormone (AMH)) were measured using morning blood samples. Symptoms of hypogonadism (depressive symptoms, fatigue, decreased libido and erectile dysfunction) were recorded systematically. Results Former AAS abusers exhibited significantly lower median (25th –75th percentiles) total and free testosterone levels than control participants (total testosterone: 14.4 (11.9–17.7) nmol/l vs. 18.8 (16.6–22.0) nmol/l) (P < 0.01). Overall, 27.2% (13.3; 45.5) of former AAS abusers exhibited plasma total testosterone levels below the lower reference limit (12.1 nmol/l) whereas no control participants exhibited testosterone below this limit (P < 0.01). Gonadotropins were significantly suppressed, and inhibin B and AMH were significantly decreased in current AAS abusers compared with former AAS abusers and control participants (P < 0.01). The group of former AAS abusers had higher proportions of participants with depressive symptoms ((24.2%) (11.1; 42.2)), erectile dysfunction ((27.3%) (13.3; 45.6)) and decreased libido ((40.1%) (23.2; 57.0)) than the other two groups (trend analyses: P < 0.05). Conclusions Former AAS abusers exhibited significantly lower plasma testosterone levels and higher frequencies of symptoms suggestive of hypogonadism than healthy control participants years after AAS cessation

  14. Efficacy of FurosapTM, a novel Trigonella foenum-graecum seed extract, in Enhancing Testosterone Level and Improving Sperm Profile in Male Volunteers

    PubMed Central

    Maheshwari, Anuj; Verma, Narsingh; Swaroop, Anand; Bagchi, Manashi; Preuss, Harry G.; Tiwari, Kiran; Bagchi, Debasis

    2017-01-01

    Background: Dietary fiber rich fenugreek (Trigonella foenum-graecum) seeds have exhibited cardioprotective, hypolipidemic and other health benefits. Furosap (FS), an innovative, patented, 20% protodioscin-enriched extract was developed in our laboratory from fenugreek seeds. This study examined the free and total testosterone levels, sperm profile and morphology, sexual health, mood and mental alertness, and broad spectrum safety parameters of FS in 50 male volunteers following supplementation over a period of 12 weeks. Methods: Institutional Review Board (IRB) and other regulatory approvals were obtained for our study. This one-arm, open-labelled, multi-center study was conducted in 50 male volunteers (age: 35 to 65 years) over a period of 12 weeks to determine the efficacy of FS (500 mg/day/subject) on free and total testosterone levels, sperm profile, sperm morphology, libido and sexual health, mood and mental alertness, and broad spectrum safety parameters. Results: Free testosterone levels were improved up to 46% in 90% of the study population. 85.4% of the study population showed improvements in sperm counts. Sperm morphology improved in 14.6% of volunteers. Majority of the subjects enrolled in the study demonstrated improvements in mental alertness and mood. Furthermore, cardiovascular health and libido were significantly improved. Extensive safety parameters were evaluated which included blood chemistry data. No significant changes were observed in serum lipid function, cholesterol, triglyceride, HDL and LDL levels, hemogram (CBC), hepatotoxicity and nephrotoxicity. Conclusion: Overall, the results demonstrate that FS, enriched in 20% protodioscin, is safe and effective in attenuating testosterone levels, healthy sperm profile, mental alertness, cardiovascular health and overall performance in human subjects. PMID:28138310

  15. Ascorbic acid treatment elevates follicle stimulating hormone and testosterone plasma levels and enhances sperm quality in albino Wistar rats

    PubMed Central

    Okon, Uduak Akpan; Utuk, Ikponoabasi Ibanga

    2016-01-01

    Background: Infertility issues have been linked to the effect of oxidative reaction in the reproductive system. This study evaluated the effect of ascorbic acid, on fertility parameters of male albino Wistar rats was studied. Materials and Methods: Eighteen albino Wistar rats weighed between 178 g and 241 g were used, randomly assigned into three groups. Group 1 was the control group; oral gavaged 5 ml of distilled water; Groups 2 and 3 were administered medium dose (250 mg/kg) and high dose of ascorbic acid (400 mg/kg), respectively; twice daily for 21 days. Blood samples were obtained by cardiac puncture, and blood serum was obtained for hormonal assay, and the testes were harvested for sperm analysis. Results: Follicle stimulating hormone levels significantly increased in the high-dose group as compared to both the control and medium dose groups. Luteinizing hormone levels in the medium dose group decreased significantly as compared to the control group. Testosterone significantly increased in both the medium- and high-dose groups as compared to the control group. Sperm motility increased significantly in the high-dose group as compared to both control and medium-dose groups. Percentage sperm concentration decreased significantly in the medium-dose group when compared to the control and increased significantly in the high-dose group as compared to the medium-dose group. For percentage normal morphology, there was a dose-dependent increase in the test groups when compared to control group. Conclusion: These results are indicative of a positive influence of ascorbic acid on male fertility modulators and may therefore, serve as a potential adjuvant treatment for male infertility cases. PMID:27185976

  16. Changes in Men’s Salivary Testosterone and Cortisol Levels, and in Sexual Desire after Smelling Female Axillary and Vulvar Scents

    PubMed Central

    Cerda-Molina, Ana Lilia; Hernández-López, Leonor; de la O, Claudio E.; Chavira-Ramírez, Roberto; Mondragón-Ceballos, Ricardo

    2013-01-01

    Several studies have shown that a woman’s vaginal or axillary odors convey information on her attractivity. Yet, whether such scents induce psychoneuroendocrinological changes in perceivers is still controversial. We studied if smelling axillary and vulvar odors collected in the periovulatory and late luteal phases of young women modify salivary testosterone and cortisol levels, as well as sexual desire in men. Forty-five women and 115 men, all of them college students and unacquainted with each other, participated in the study. Female odors were collected on pads affixed to the axilla and on panty protectors both worn the entire night before experiments. Men provided five saliva samples, a basal one before the smelling procedure, and four more 15, 30, 60, and 75 min after exposure to odors. Immediately after smelling the odor source, men answered a questionnaire rating hedonic qualities of scents, and after providing the last saliva sample they answered questionnaire on sexual desire. We found that periovulatory axillary and vulvar odors increased testosterone and cortisol levels, with vulvar scents producing a more prolonged effect. Luteal axilla odors decreased testosterone and cortisol levels, while luteal vulva odors increased cortisol. Periovulatory axilla and vulva scents accounted for a general increase of interest in sex. These odors were also rated as more pleasant and familiar, while luteal vulvar odors were perceived as intense and unpleasant. PMID:24194730

  17. Early sexual maturity in local boars of Northeastern India: age-related changes in testicular growth, epididymal sperm characteristics and peripheral testosterone levels.

    PubMed

    Kumaresan, A; Bujarbaruah, K M; Kadirvel, G; Khargharia, G; Sarma, Rumi G; Goswami, J; Basumatary, Rantu; Palaniappan, Kavitha; Bardoloi, R K

    2011-03-01

    The present study reports the age related changes in the peripheral testosterone levels, testicular and epididymal growth and development and cauda epididymal spermiogram in local pigs of Northeastern India, which attain sexual maturity around 3 months of age. Local boars (n = 20) were castrated at monthly intervals from 2 to 6 months of age (4 boars per month) to study the testicular growth and development and the epididymal spermiogram. Blood samples, collected from local boars (n = 6) at monthly intervals from 2 to 6 months of age, were analyzed for testosterone levels by radioimmunoassay. Compared to Hampshire boars, significantly (P < 0.05) high testosterone levels were observed in the local boars as early as 2 months of age. The mean (± SEM) level of testosterone in the local boars at 2, 3 and 4 months of age was 11.89 ± 1.52, 20.45 ± 1.33 and 20.38 ± 2.0 ngml(-1), respectively. Though there was consistently significant (P < 0.05) difference in the body weight between Hampshire and local pigs, the same was not observed in case of testicular weight except at 3 and 6 months of age. In line with the above observation, the testis:body weight ratio (gram testis per kg body weight) was significantly (P < 0.05) higher in the local boars compared to the Hampshire boars at any time of observation, which ranged from 0.8 to 1.0 in case of Hampshire and from 2.3 to 3.0 in local boars. The sperm concentration in the cauda epididymal fluid of local boars at 2, 3 and 6 months of age was 2255 ± 186.6, 3685 ± 103.8 and 4325 ± 146.2 million/ml, respectively and the sperm motility, viability and total abnormality was 73.3, 75.2 and 6.2%, respectively at 3 months of age. Taken together, the testosterone level, testicular growth and development and epididymal spermiogram indicate the trait of early sexual maturity in the local pigs as compared to Hampshire.

  18. Lack of effects of a lyposterolic extract of Serenoa repens on plasma levels of testosterone, follicle-stimulating hormone, and luteinizing hormone.

    PubMed

    Casarosa, C; Cosci di Coscio, M; Fratta, M

    1988-01-01

    Twenty men, aged 50 to 75 years (mean, 67 years), suffering from benign prostatic hypertrophy received 160 mg of a lyposterolic extract of Serenoa repens, twice daily for 30 days. Before and at the end of treatment, plasma levels of testosterone, follicle-stimulating hormone, and luteinizing hormone were determined. No changes in plasma hormone levels occurred as a result of treatment. It is concluded that Serenoa extract, which is useful in the treatment of benign prostatic hypertrophy, does not act via systemic changes of hormone levels.

  19. The effect of combined oral contraception on testosterone levels in healthy women: a systematic review and meta-analysis

    PubMed Central

    Zimmerman, Y.; Eijkemans, M.J.C.; Coelingh Bennink, H.J.T.; Blankenstein, M.A.; Fauser, B.C.J.M.

    2014-01-01

    BACKGROUND Combined oral contraceptives (COCs) reduce levels of androgen, especially testosterone (T), by inhibiting ovarian and adrenal androgen synthesis and by increasing levels of sex hormone-binding globulin (SHBG). Although this suppressive effect has been investigated by numerous studies over many years, to our knowledge no systematic review concerning this issue had been performed. This systematic review and meta-analysis was performed to evaluate the effect of COCs on concentrations of total T, free T and SHBG in healthy women and to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T and free T. METHODS A review of the literature was performed using database searches (MEDLINE, EMBASE and the Cochrane Central Register of Clinical Trials) and all publications (from inception date until July 2012) investigating the effect of COCs on androgen levels in healthy women were considered eligible for selection. Three reviewers were involved in study selection, data extraction and critical appraisal. For the meta-analysis, data on total T, free T and SHBG were extracted and combined using random effects analysis. Additional subgroup analyses were performed to evaluate differences between the various types of COCs (e.g. estrogen dose, type of progestin) and the assays used to assess total T or free T. RESULTS A total of 151 records were identified by systematic review and 42 studies with a total of 1495 healthy young women (age range: 18–40 years) were included in the meta-analysis. All included studies were experimental studies and 21 were non-comparative. Pooling of the results derived from all the included papers showed that total T levels significantly decreased during COC use [mean difference (MD) (95% confidence interval, CI) −0.49 nmol/l (−0.55, −0.42); P < 0.001]. Significantly lower levels of free T were also found [relative change (95% CI) 0.39 (0.35, 0.43); P < 0

  20. Protective effect of royal jelly on the sperm parameters and testosterone level and lipid peroxidation in adult mice treated with oxymetholone

    PubMed Central

    Zahmatkesh, Ensieh; Najafi, Gholamreza; Nejati, Vahid; Heidari, Reza

    2014-01-01

    Objectives : The aim of the present study was to evaluate protective effect of royal jelly on sperm parameters, testosterone level, and malondialdehyde (MDA) production in mice. Materials and Methods: Thirty-two adult male NMRI mice weighing 30±2 g were used. All the animals were divided into 4 groups. Control group: received saline 0.1 ml/mouse/day orally for 30 days. Royal jelly group (RJ): received royal jelly at dose of 100 mg/kg daily for 30 days orally. Oxymetholone group: the received Oxymetholone (OX) at dose of 5 mg/kg daily for 30 days orally. Royal jelly+Oxymetholone group: received royal jelly at dose of 100 mg/kg/day orally concomitant with OX administration. Sperm count, sperm motility, viability, maturity, and DNA integrity were analyzed. Furthermore, serum testosterone and MDA concentrations were determined. Results: In Oxymetholone group, sperm count, motility as well as testosterone concentration reduced significantly (p<0.05), while significant (p<0.05) increases in immature sperm, sperm with DNA damaged, and MDA concentration were announced in Oxymetholone group in comparison with control group and Royal jelly+Oxymetholone group. RJ caused partially amelioration in all of the above- mentioned parameters in Royal Jelly+Oxymetholone group. Conclusion: In conclusion, RJ may be used in combination with OX to improve OX-induced oxidative stress and male infertility. PMID:25050300

  1. Comparison of the Effects of Resistance Exercise Orders on Number of Repetitions, Serum IGF-1, Testosterone and Cortisol Levels in Normal-Weight and Obese Men

    PubMed Central

    Sheikholeslami-Vatani, Dariush; Ahmadi, Slahadin; Salavati, Rashad

    2016-01-01

    Background: Exercise order affects repetition performance and acute hormonal responses to resistance training (RT) programs. Objectives: The purpose of this study was to compare the acute effects of two different resistance exercise orders (REO) on number of repetitions and serum Insulin-like Growth Factor-1 (IGF-1), testosterone and cortisol levels in normal-weight and obese men. Materials and Methods: 25 untrained college-aged men were assigned to either obese (n = 11) or normal-weight (n = 15) groups. Subjects performed two REO protocols in 2 exercise groups. In the first group subjects began with large-muscle group and progressed to small-muscle group (Protocol A), while in the other group subjects performed the same exercise but in reverse sequence (Protocol B). Each activity was performed in 3 consecutive sets of 10 repetitions maximum to near fatigue. Results: REOs did not affect number of repetitions in none of the groups. The average rating of perceived exertion was higher for protocol B in both groups. IGF-1 and testosterone increased immediately post exercise for both protocols and in both groups, however immediately post exercise increase in IGF-1 and testosterone were lower in obese group. Cortisol response to REO was weaker in obese group. Conclusions: Performing large muscle group exercises first in RE training and progressing to small muscle group produced greater anabolic hormonal response relative to reverse sequence in normal-weight young adult men. Anabolic hormonal response to REOs was blunted in the obese group. PMID:27217934

  2. Effects of PCBs on plasma enzymes, testosterone level, and hepatic xenobiotic metabolism in the grey partridge, perdix perdlx

    SciTech Connect

    Abiola, F. ); Lorgue, G.; Riviere, J.L. ); Benoit, E. ); Soyez, D. )

    1989-09-01

    The hepatic cytochrome P-450-dependent monooxygenase (MO) system functions in oxidative biotransformation of a wide variety of both endogenous and exogenous (xenobiotic) compounds in many animal species. However, most of the previous studies were carried out with a narrow range of species and investigations on wild species are lacking. In this report, the authors describe the effects of a commercial mixture of PCBs (DP5) on the hepatic MO activities of the grey partridge (Perdix perdix). To more thoroughly investigate the inducing effects of DP5, they used two series of homologous substrates, alkylresorufins and alkoxycoumarins, and an endogenous compound, testosterone, which were shown in mammals to differentiate between different forms of cytochrome P-450. Furthermore, to more carefully assess the effects of DP5, they also measured the activity of two plasma marker enzymes, alanine transpeptidase (ALAT) and gamma-glutamyl transferase (gamma-GT), and the plasmatic concentration of testosterone.

  3. The effect of boron supplementation on lean body mass, plasma testosterone levels, and strength in male bodybuilders

    NASA Technical Reports Server (NTRS)

    Ferrando, A. A.; Green, N. R.

    1993-01-01

    The effect of boron supplementation was investigated in 19 male bodybuilders ages 20-27 years. Ten were given a 2.5-mg boron supplement while 9 were given a placebo every day for 7 weeks. Plasma total and free testosterone, plasma boron, lean body mass, and strength measurements were determined on Days 1 and 49 of the study. Plasma boron values were significantly (p < 0.05) different as the experimental group increased from (+/- SD) 20.1 +/- 7.7 ppb pretest to 32.6 +/- 27.6 ppb posttest, while the control group mean decreased from 15.1 +/- 14.4 ppb pretest to 6.3 +/- 5.5 ppb posttest. Analysis of variance indicated no significant effect of boron supplementation on any of the dependent variables. Both groups demonstrated significant increases in total testosterone, lean body mass, 1-RM squat, and 1-RM bench press. The findings suggest that 7 weeks of bodybuilding can increase total testosterone, lean body mass, and strength in lesser trained bodybuilders, and that boron supplementation had no effect on these measures.

  4. Suppression of human spermatogenesis by testosterone implants.

    PubMed

    Handelsman, D J; Conway, A J; Boylan, L M

    1992-11-01

    Hormonally induced azoospermia is an effective, reversible form of male contraception; however, some men treated with weekly im testosterone enanthate (TE) injections fail to become azoospermic. As weekly injections cause widely fluctuating and supraphysiological testosterone levels, we tested the hypothesis that more stable, physiological testosterone levels would consistently produce azoospermia. Using a depot testosterone formulation which provides stable, physiological range testosterone levels for up to 6 months, we studied nine men before and after insertion of six 200 mg testosterone implants under the abdominal wall skin and compared the results with 38 men treated in a previous study with weekly im injections of 200 mg TE. Testosterone implants suppressed sperm output to near-azoospermia between the second to fourth postimplant months returning to normal by the sixth postimplant month. The fall in sperm output at the first month was greater after testosterone implants than TE injections (58% vs. 17%, P = 0.011) but similar proportions of men became azoospermic (5/9 vs. 25/38) or severely oligozoospermic (< 1 million/ml; 9/9 vs. 37/38). Plasma testosterone and estradiol levels remained mostly within the eugonadal range after implants but were markedly supraphysiological during TE injections. Both treatments suppressed immunoreactive LH and FSH to undetectable levels by ultrasensitive fluoroimmunoassay. Sex hormone-binding globulin levels were decreased and PRL levels increased by TE injections but neither was changed by testosterone implants. Prostate-specific antigen demonstrated a small rise of marginal significance (P = 0.065) after testosterone implants. Fewer men experienced acne after implants (0/9 vs. 25/38, p = 0.0004). Therefore a depot testosterone preparation with quasi-zero-order release demonstrates higher dose efficiency with similar (but not uniform) efficacy at inducing azoospermia but may cause fewer androgenic side-effects than weekly TE

  5. Testosterone perturbs epidermal permeability barrier homeostasis.

    PubMed

    Kao, J S; Garg, A; Mao-Qiang, M; Crumrine, D; Ghadially, R; Feingold, K R; Elias, P M

    2001-03-01

    Although there are no known gender-related differences in permeability barrier function in adults, estrogens accelerate whereas testosterone retards barrier development in fetal skin, and male fetuses demonstrate slower barrier development than female littermates. Moreover, prenatal administration of the androgen receptor antagonist, flutamide, equalizes developmental rates in male and female fetuses. Therefore, we evaluated the effects of changes in testosterone on barrier homeostasis in adult murine and human skin. Hypogonadal mice (whether by castration or by treatment with systemic flutamide) displayed significantly faster barrier recovery at 3, 6, and 12 h than did controls, and testosterone replacement slowed barrier recovery in castrated mice. Moreover, testosterone directly effects the skin, as topical flutamide also accelerated barrier recovery in normal male mice. These findings appear to be of physiologic significance, since prepubertal male mice (age 5 wk) displayed accelerated barrier recovery in comparison with adult postpubertal (11 wk) males. These studies also appear to be relevant for humans, as a hypopituitary human subject demonstrated repeated changes in barrier recovery in parallel with peaks and nadirs in serum testosterone levels during intermittent testosterone replacement. Mechanistic studies showed that differences in epidermal lipid synthesis do not account for the testosterone-induced functional alterations. Instead, epidermal lamellar body (LB) formation and secretion both decrease, resulting in decreased extracellular lamellar bilayers in testosterone-replete animals. These studies demonstrate that fluctuations in testosterone modulate barrier function, and that testosterone repletion can have negative consequences for permeability barrier homeostasis.

  6. Effect of aqueous and hydro-alcoholic extracts of lettuce (Lactuca sativa) seed on testosterone level and spermatogenesis in NMRI mice

    PubMed Central

    Ahangarpour, Akram; Oroojan, Ali Akbar; Radan, Maryam

    2014-01-01

    Background: One of the considerable uses of lettuce (Lactuca sativa) seed in traditional medicine has been to reduce semen, sperm and sexuality. Objective: The aim of this study was to investigate the effects of aqueous and hydro-alcoholic extracts of lettuce seed on testosterone level and spermatogenesis. Materials and Methods: In this experimental study 24 adult male NMRI mice weighing 20-25gr were purchased. Animals were randomly divided into 4 groups: controls, hydro-alcoholic (200 mg/kg) and aqueous extracts (50, 100mg/kg). The extracts were injected intraperitoneally once a day for 10 consecutive days. 2 weeks after the last injection, the mice were anaesthetized by ether and after laparatomy blood was collected from the heart to determine testosterone by ELISA assay kit. Then testis and cauda epididymis of all animals were removed for analyzing testis morphology and sperm count and viability. Results: Testis weight in hydro-alcoholic and aqueous extracts 100 mg/kg (p=0.001) and aqueous extract 50 mg/kg (p=0.008) groups was increased. Sperm viability in hydro-alcoholic (p=0.001) and aqueous extracts 50 (p=0.026), 100 mg/kg (p=0.045) groups was decreased, Also the results showed a significant decrease in sperm count in hydro-alcoholic (p=0.035) and aqueous extracts 50 mg/kg (p=0.006) groups in comparison with control group. Also there was a significant increase in serum level of testosterone in aqueous extract 50 mg/kg group in comparison with control (p=0.002) hydro-alcoholic (p=0.001) and aqueous extracts 100 mg/kg (p=0.003) groups. Conclusion: Present results demonstrated that hydro-alcoholic and aqueous 50 mg/kg extracts of lettuce seed have antispermatogenic effects, also aqueous extract 50 mg/kg increased serum level of testosterone in mice. Therefore we can suggest that lettuce seed could be a potential contraceptive agent. This article extracted from M.Sc. student research project. (Ali Akbar Oroojan) PMID:24799863

  7. Testosterone Regulates Bone Response to Inflammation

    PubMed Central

    Steffens, J. P.; Herrera, B. S.; Coimbra, L. S.; Stephens, D. N.; Rossa, C.; Spolidorio, L. C.; Kantarci, A.; Van Dyke, T. E.

    2015-01-01

    This study evaluated the alveolar bone response to testosterone and the impact of Resolvin D2 (RvD2) on testosterone-induced osteoblast function. For the in vivo characterization, 60 male adult rats were used. Treatments established sub-physiologic (L), normal (N), or supra-physiologic (H) concentrations of testosterone. Forty rats were subjected to orchiectomy; 20 rats received periodical testosterone injections while 20 rats received testicular sham-operation. Four weeks after the surgeries, 10 rats in each group received a subgingival ligature around the lower first molars to induce experimental periodontal inflammation and bone loss. In parallel, osteoblasts were differentiated from neonatal mice calvariae and treated with various doses of testosterone for 48 h. Cell lysates and conditioned media were used for the determination of alkaline phosphatase, osteocalcin, RANKL, and osteoprotegerin. Micro-computed tomography linear analysis demonstrated that bone loss was significantly increased for both L and H groups compared to animals with normal levels of testosterone. Gingival IL-1β expression was increased in the L group (p < 0.05). Ten nM testosterone significantly decreased osteocalcin, RANKL, and OPG levels in osteoblasts; 100 nM significantly increased the RANKL:OPG ratio. RvD2 partially reversed the impact of 10 nM testosterone on osteocalcin, RANKL, and OPG. These findings suggest that both L and H testosterone levels increase inflammatory bone loss in male rats. While low testosterone predominantly increases the inflammatory response, high testosterone promotes a higher osteoblast-derived RANKL:OPG ratio. The proresolving mediator RvD2 ameliorates testosterone-derived downregulation of osteocalcin, RANKL, and OPG in primary murine osteoblasts suggesting a direct role of inflammation in osteoblast function. PMID:24526374

  8. Effects of dutasteride on lower urinary tract symptoms: a prospective analysis based on changes in testosterone/dihydrotestosterone levels and total prostatic volume reduction.

    PubMed

    Shigehara, Kazuyoshi; Miyagi, Tohru; Nakashima, Takao; Izumi, Koji; Kitagawa, Yasuhide; Mizokami, Atsushi; Koh, Eitetsu; Shimamura, Masayoshi; Namiki, Mikio

    2016-06-01

    This study analyzed the effects of dutasteride on lower urinary tract symptoms based on the association between changes in the total testosterone (TT)/dihydrotestosterone (DHT) levels and total prostate volume (TPV) reduction. Sixty participants diagnosed with benign prostatic hyperplasia were given 0.5 mg of dutasteride daily for 52 weeks. Measures of TT and DHT levels, TPV and uroflowmetry were obtained before and after dutasteride treatment. Forty-three patients demonstrated a TPV reduction of ≥5% (Group 1), whereas the remaining 17 patients demonstrated a TPV reduction of <5% (Group 2). DHT suppression and DHT/TT ratio at baseline were significantly higher in Group 1 than Group 2. International Prostate Symptom Scores (IPSS) and uroflowmetry were significantly improved in both groups. In Group 2, nine patients demonstrated some improvement in IPSS (Group 2A), whereas eight did not (Group 2B). The rate of TT increase and improvement in voiding symptoms were significantly higher in Group 2A than Group 2B. Dutasteride-induced TPV reduction is dependent on individual 5-α reductase inhibitor activity. Some patients demonstrating smaller dutasteride-induced TPV reduction may experience an improvement in voiding symptoms owing to an increased level of testosterone.

  9. Effect of different levels and sources of zinc supplementation on quantitative and qualitative semen attributes and serum testosterone level in crossbred cattle (Bos indicus x Bos taurus) bulls.

    PubMed

    Kumar, Nishant; Verma, Ramesh Prashad; Singh, Lallan Prasad; Varshney, Vijay Prakash; Dass, Ram Sharan

    2006-01-01

    An experiment was conducted on 16 crossbred bulls (about 2 years of age, 316.2+/-0.77 kg average body weight), divided into groups I, II, III and IV to study the effect of different levels of Zn supplementation from inorganic and organic sources on semen quality. The animals in the first 3 groups were supplemented with 0, 35 and 70 ppm Zn from Zn sulfate, respectively and the animals in-group IV were supplemented with 35 ppm Zn as Zn propionate. Semen collection and evaluation was done in the first month (to assess semen quality at the start of the experiment) and 7th, 8th and 9th month of experimental feeding to evaluate the effect of supplemental Zn on semen attributes. We gave 6 months for Zn feeding, so that 3 sperm cycles of spermatogenesis had passed and the collected semen reflected the complete effect of Zn supplementation. Six ejaculates from each bull were collected and evaluated for semen quantitative (ejaculate volume, sperm concentration and sperm number per ejaculate) and qualitative characteristics (semen pH, mass motility, individual motility, sperm livability percent and abnormal sperm percent, percent intact acrosome, bovine cervical mucus penetration test, hypo-osmotic sperm swelling test) and activity of seminal plasma enzymes i.e., alkaline phosphatase, acid phosphatase, GOT and GPT. Testosterone level in the blood serum of crossbred bulls was also estimated. Mean values of semen quantitative and qualitative characteristics at the start of the experiment were statistically non significant (P > 0.05) in all the crossbred cattle bulls, however, there were statistically significant differences among the bulls of different groups after 6 months of zinc supplementation. Mean ejaculate volume (mL) was 2.37, 4.70, 5.86 and 6.38, respectively in groups I to IV, indicating a statistically significant (P < 0.05) higher semen volume in Zn-supplemented groups as compared to the control group of bulls. Similarly, sperm concentration (million.mL(-1)), live

  10. Testosterone and metabolic syndrome.

    PubMed

    Cunningham, Glenn R

    2015-01-01

    Controversies surround the usefulness of identifying patients with the metabolic syndrome (MetS). Many of the components are accepted risk factors for cardiovascular disease (CVD). Although the MetS as defined includes many men with insulin resistance, insulin resistance is not universal. The low total testosterone (TT) and sex hormone binding globulin (SHBG) levels in these men are best explained by the hyperinsulinism and increased inflammatory cytokines that accompany obesity and increased waist circumference. It is informative that low SHBG levels predict future development of the MetS. Evidence is strong relating low TT levels to CVD in men with and without the MetS; however, the relationship may not be causal. The recommendations of the International Diabetes Federation for managing the MetS include cardiovascular risk assessment, lifestyle changes in diet, exercise, weight reduction and treatment of individual components of the MetS. Unfortunately, it is uncommon to see patients with the MetS lose and maintain a 10% weight loss. Recent reports showing testosterone treatment induced dramatic changes in weight, waist circumference, insulin sensitivity, hemoglobin A1c levels and improvements in each of the components of the MetS are intriguing. While some observational studies have reported that testosterone replacement therapy increases cardiovascular events, the Food and Drug Administration in the United States has reviewed these reports and found them to be seriously flawed. Large, randomized, placebo-controlled trials are needed to provide more definitive data regarding the efficacy and safety of this treatment in middle and older men with the MetS and low TT levels.

  11. Delivering enhanced testosterone replacement therapy through nanochannels.

    PubMed

    Ferrati, Silvia; Nicolov, Eugenia; Bansal, Shyam; Zabre, Erika; Geninatti, Thomas; Ziemys, Arturas; Hudson, Lee; Ferrari, Mauro; Goodall, Randal; Khera, Mohit; Palapattu, Ganesh; Grattoni, Alessandro

    2015-02-18

    Primary or secondary hypogonadism results in a range of signs and symptoms that compromise quality of life and requires life-long testosterone replacement therapy. In this study, an implantable nanochannel system is investigated as an alternative delivery strategy for the long-term sustained and constant release of testosterone. In vitro release tests are performed using a dissolution set up, with testosterone and testosterone:2-hydroxypropyl-β-cyclodextrin (TES:HPCD) 1:1 and 1:2 molar ratio complexes release from the implantable nanochannel system and quantify by HPLC. 1:2 TES:HPCD complex stably achieve 10-15 times higher testosterone solubility with 25-30 times higher in vitro release. Bioactivity of delivered testosterone is verified by LNCaP/LUC cell luminescence. In vivo evaluation of testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels by liquid chromatography mass spectrometry (LC/MS) and multiplex assay is performed in castrated Sprague-Dawley rats over 30 d. Animals are treated with the nanochannel implants or degradable testosterone pellets. The 1:2 TES:HPCD nanochannel implant exhibits sustained and clinically relevant in vivo release kinetics and attains physiologically stable plasma levels of testosterone, LH, and FSH. In conclusion, it is demonstrated that by providing long-term steady release 1:2 TES:HPCD nanochannel implants may represent a major breakthrough for the treatment of male hypogonadism.

  12. Testosterone treatment of hypogonadal men participating in competitive sports.

    PubMed

    Gooren, L J; Behre, H M

    2008-06-01

    Testosterone has a steeply dose-dependent effect on muscle mass and strength irrespective of gonadal status. So, for reasons of fairness, people who engage in competitive sports should not administer exogenous testosterone raising their blood testosterone levels beyond the range of normal. There is a ban on exogenous androgens for men and women in sports, but an exception has been made for men with androgen deficiency due to pituitary or testicular disease. Men who receive testosterone administration for the indication hypogonadism have an interest in the use of testosterone preparations generating blood testosterone levels within the normal range of healthy, eugonadal men. On the grounds of a positive correlation between blood testosterone concentrations muscle and volume/strength, they are best served with a parenteral testosterone preparation, rather than transdermal testosterone, but they should not run the risk of being excluded from competition because of supraphysiological testosterone levels. The latter is a realistic risk with the traditional parenteral testosterone esters. The new parenteral testosterone undecanoate preparation offers much better perspectives. Its pharmacokinetics have been investigated in detail and there is a fair degree of predictability of resulting blood testosterone levels with use of this preparation.

  13. Assessing bioavailability levels of metals in effluent-affected rivers: effect of Fe(III) and chelating agents on the distribution of metal speciation.

    PubMed

    Han, Shuping; Naito, Wataru; Masunaga, Shigeki

    To assess the effects of Fe(III) and anthropogenic ligands on the bioavailability of Ni, Cu, Zn, and Pb, concentrations of bioavailable metals were measured by the DGT (diffusive gradients in thin films) method in some urban rivers, and were compared with concentrations calculated by a chemical equilibrium model (WHAM 7.0). Assuming that dissolved Fe(III) (<0.45 μm membrane filtered) was in equilibrium with colloidal iron oxide, the WHAM 7.0 model estimated that bioavailable concentrations of Ni, Cu, and Zn were slightly higher than the corresponding values estimated assuming that dissolved Fe(III) was absent. In contrast, lower levels of free Pb were predicted by the WHAM 7.0 model when dissolved Fe(III) was included. Estimates showed that most of the dissolved Pb was present as colloidal iron-Pb complex. Ethylene-diamine-tetra-acetic acid (EDTA) concentrations at sampling sites were predicted from the relationship between EDTA and the calculated bioavailable concentration of Zn. When both colloidal iron and predicted EDTA concentrations were included in the WHAM 7.0 calculations, dissolved metals showed a strong tendency to form EDTA complexes, in the order Ni > Cu > Zn > Pb. With the inclusion of EDTA, bioavailable concentrations of Ni, Cu, and Zn predicted by WHAM 7.0 were different from those predicted considering only humic substances and colloidal iron.

  14. Sexual Health: Testosterone Therapy

    MedlinePlus

    Healthy Lifestyle Sexual health Considering testosterone therapy to help you feel younger and more vigorous as you age? ... 01, 2015 Original article: http://www.mayoclinic.org/healthy-lifestyle/sexual-health/in-depth/testosterone-therapy/art-20045728 . ...

  15. Herbal modulation of drug bioavailability: enhancement of rifampicin levels in plasma by herbal products and a flavonoid glycoside derived from Cuminum cyminum.

    PubMed

    Sachin, B S; Sharma, S C; Sethi, S; Tasduq, S A; Tikoo, M K; Tikoo, A K; Satti, N K; Gupta, B D; Suri, K A; Johri, R K; Qazi, G N

    2007-02-01

    The bioavailability of rifampicin (RIF) in a fixed dose combination (FDC) used for the treatment of tuberculosis remains an area of clinical concern and several pharmaceutical alternatives are being explored to overcome this problem. The present study presents a pharmacological approach in which the bioavailability of a drug may be modulated by utilizing the herb-drug synergism. The pharmacokinetic interaction of some herbal products and a pure molecule isolated from Cuminum cyminum with RIF is shown in this paper. An aqueous extract derived from cumin seeds produced a significant enhancement of RIF levels in rat plasma. This activity was found to be due to a flavonoid glycoside, 3',5-dihydroxyflavone 7-O-beta-D-galacturonide 4'-O-beta-D-glucopyranoside (CC-I). CC-I enhanced the Cmax by 35% and AUC by 53% of RIF. The altered bioavailability profile of RIF could be attributed to a permeation enhancing effect of this glycoside.

  16. Andropause. Testosterone replacement therapy for aging men.

    PubMed Central

    Bain, J.

    2001-01-01

    OBJECTIVE: To review the rationale for treating symptomatic aging men whose testosterone levels are mildly reduced or low-normal with testosterone replacement therapy. QUALITY OF EVIDENCE: Large-scale multicentre prospective studies on the value of treating andropausal men with hormone therapy do not exist because the whole area of hormone therapy is barely 10 years old. Evidence presented is based on physiologic studies, particularly studies in which treatment has been assessed. These were largely uncontrolled open studies. Studies to date report positive responses to testosterone treatment with very few serious side effects. MAIN MESSAGE: Physicians should consider hypoandrogenism if male patients complain of loss of libido, erectile dysfunction, weakness, fatigue, lethargy, loss of motivation, or mood swings. Less obvious associations with reduced levels of testosterone are anemia and osteoporosis. The main cause of reduced testosterone production is primary gonadal insufficiency, but secondary causes, such as hypothalamic-pituitary disease, should be considered. Evidence shows that most men treated with testosterone will feel better about themselves and their lives. CONCLUSION: Andropause is a term of convenience describing a complex of symptoms in aging men who have low testosterone levels. Physicians should be aware of its existence, should consider ordering tests for men who have symptoms, and should treat carefully selected patients whose serum testosterone levels are low. PMID:11212438

  17. [Testosterone deficiency, metabolic syndrome and diabetes mellitus].

    PubMed

    Fernández-Miró, Mercè; Chillarón, Juan J; Pedro-Botet, Juan

    2016-01-15

    Testosterone deficiency in adult age is associated with a decrease in libido, energy, hematocrit, muscle mass and bone mineral density, as well as with depression. More recently, testosterone deficiency has also been associated with various components of the metabolic syndrome, which in turn is associated with a five-fold increase in the risk of cardiovascular disease. Low testosterone levels are associated with increased insulin resistance, increase in fat mass, low HDL cholesterol, higher triglyceride levels and hypertension. Testosterone replacement therapy in patients with testosterone deficiency and type 2 diabetes mellitus and/or metabolic syndrome has shown reductions in insulin resistance, total cholesterol, LDL cholesterol and triglycerides and improvement in glycemic control and anthropometric parameters.

  18. Effects of varicocelectomy on serum testosterone

    PubMed Central

    Whelan, Patrick

    2016-01-01

    Varicocele is most often surgically repaired due to male infertility, however, has recently been linked to low serum testosterone. This paper serves to review the current literature regarding varicocele and its subsequent repair on serum testosterone. Twenty-eight human studies were identified with fifteen showing improved serum testosterone after repair. The majority of the studies that demonstrated improvement had preoperative testosterone levels that were low or below normal. Additionally, multiple well-designed studies with control groups not undergoing surgical repair demonstrated significant difference between groups. This improvement was less observed in studies with normal preoperative serum testosterone. A majority of these patients studied were presenting for infertility. It remains to be determined if these findings can be reproduced in men without infertility. The findings suggest that microsurgical varicocele repair can improve serum testosterone in men with low levels preoperatively in appropriately counseled men. It remains to be seen whether varicocele repair can help prevent the development of low testosterone in the future or which patients are at risk of developing low testosterone due to varicocele. PMID:28078218

  19. Serum Testosterone Kinetics After Brachytherapy for Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan H.; Allen, Zachariah A.; Wallner, Kent E.

    2012-01-01

    Purpose: To evaluate temporal changes in testosterone after prostate brachytherapy and investigate the potential impact of these changes on response to treatment. Methods and Materials: Between January 2008 and March 2009, 221 consecutive patients underwent Pd-103 brachytherapy without androgen deprivation for clinically localized prostate cancer. Prebrachytherapy prostate-specific antigen (PSA) and serum testosterone were obtained for each patient. Repeat levels were obtained 3 months after brachytherapy and at least every 6 months thereafter. Multiple clinical, treatment, and dosimetric parameters were evaluated to determine an association with temporal testosterone changes. In addition, analysis was conducted to determine if there was an association between testosterone changes and treatment outcomes or the occurrence of a PSA spike. Results: There was no significant difference in serum testosterone over time after implant (p = 0.57). 29% of men experienced an increase {>=}25%, 23% of men experienced a decrease {>=}25%, and the remaining 48% of men had no notable change in testosterone over time. There was no difference in testosterone trends between men who received external beam radiotherapy and those who did not (p = 0.12). On multivariate analysis, preimplant testosterone was the only variable that consistently predicted for changes in testosterone over time. Men with higher than average testosterone tended to experience drop in testosterone (p < 0.001), whereas men with average or below average baseline testosterone had no significant change. There was no association between men who experienced PSA spike and testosterone temporal trends (p = 0.50) nor between initial PSA response and testosterone trends (p = 0.21). Conclusion: Prostate brachytherapy does not appear to impact serum testosterone over time. Changes in serum testosterone do not appear to be associated with PSA spike phenomena nor with initial PSA response to treatment; therefore, PSA response

  20. Experiment K-6-16. Morphological examination of rat testes. The effect of Cosmos 1887 flight on spermatogonial population and testosterone level in rat testes

    NASA Technical Reports Server (NTRS)

    Philpott, D. E.; Kato, K.; Stevenson, J.; Vasques, M.; Sapp, W.; Williams, C.; Popova, I. A.; Serova, L. V.

    1990-01-01

    Testes from rats flown on Cosmos 1887 for twelve and a half days were compared to basal control, synchronous control and vivarium maintained rats. When the mean weights of flight testes, normalized for weight/100 gms, were compared to the vivarium controls they were 6.7 percent lighter. Although the flight testes were lighter than the synchronous, the difference is not significant. Counts of spermatogonial cells from 5 animals in each group revealed a 4 percent decrease in flight compared to vivarium controls. In both cases the t-Test significance was less than 0.02. The serum testosterone levels of all animals (flight, synchronous and vivarium) were significantly below the basal controls.

  1. Serum Testosterone Concentrations and Urinary Bisphenol A, Benzophenone-3, Triclosan, and Paraben Levels in Male and Female Children and Adolescents: NHANES 2011–2012

    PubMed Central

    Scinicariello, Franco; Buser, Melanie C.

    2016-01-01

    Background: Exposure to environmental phenols (e.g., bisphenol A, benzophenone-3, and triclosan) and parabens is widespread in the population. Many of these chemicals have been shown to have anti-androgenic effects both in vitro and in vivo. Objective: We examined the association of bisphenol A (BPA), benzophenone-3 (BP-3), triclosan (TCS), and parabens with serum total testosterone (TT) levels in child and adolescent participants (ages 6–19 years) in the National Health and Nutrition Examination Survey (NHANES) 2011–2012. Methods: We performed multivariable linear regression to estimate associations between natural log–transformed serum TT and quartiles of urinary BPA, BP-3, TCS, and parabens in male and female children (ages 6–11 years) and adolescents (ages 12–19 years). Results: BP-3 and BPA were associated with significantly lower TT in male adolescents, and BPA was associated with significantly higher TT in female adolescents. TT was not consistently associated with TCS or total parabens in children or adolescents of either sex. Conclusions: To our knowledge, this is the first study to report an association of both BP-3 and BPA with serum TT in adolescents. Associations between BPA and TT differed according to sex in adolescents, with inverse associations in boys and positive associations in girls. BP-3 was associated with significantly lower TT in adolescent boys only. However, because of the limitations inherent to the cross-sectional study design, further studies are needed to confirm and elucidate on our findings. Citation: Scinicariello F, Buser MC. 2016. Serum testosterone concentrations and urinary bisphenol A, benzophenone-3, triclosan, and paraben levels in male and female children and adolescents: NHANES 2011–2012. Environ Health Perspect 124:1898–1904; http://dx.doi.org/10.1289/EHP150 PMID:27383665

  2. Testosterone ethosomes for enhanced transdermal delivery.

    PubMed

    Ainbinder, Denize; Touitou, Elka

    2005-01-01

    Physiological decrease in testosterone levels in men with age causes various changes with clinical significance. Recent testosterone replacement therapy is based mainly on transdermal nonpatch delivery systems. These products have the drawback of application on extremely large areas to achieve required hormone blood levels. The objective of the present study was to design and test a testosterone nonpatch formulation using ethosomes for enhanced transdermal absorption. The ethosomal formulation was characterized by transmission electron microscopy and dynamic light scattering for structure and size distribution and by ultracentrifugation for entrapment capacity. To evaluate the feasibility of this delivery system to enhance testosterone permeation through the skin, first the systemic absorption in rats was compared with a currently used gel (AndroGel). Further, theoretical estimation of testosterone blood concentration following ethosomal application in men was made. For this purpose, in vitro permeation experiments through human skin were performed to establish testosterone skin permeation values. In the design of these experiments, testosterone solubility in various solutions was measured and the effect of the receiver medium on the skin barrier function was assessed by confocal laser scanning microscopy. Theoretical estimation shows that testosterone human plasma concentration value in the upper part of the physiological range could be achieved by application of the ethosomal formulation on an area of 40 cm(2). This area is about 10 times smaller than required with current nonpatch formulations. Our work shows that the ethosomal formulation could enhance testosterone systemic absorption and also be used for designing new products that could solve the weaknesses of the current testosterone replacement therapies.

  3. Contemporary perspective and management of testosterone deficiency: Modifiable factors and variable management.

    PubMed

    Hisasue, Shin-ichi

    2015-12-01

    Testosterone deficiency can occur in males of all ages. In adult males, it is induced by endogenous testosterone decline through aging and other modifiable factors. Recent publications suggested the importance of the magnitude of longitudinal decline of testosterone from baseline. The baseline level and the longitudinal decline have individual variability influenced by individual factors including digit ratio, CAG repeat of the androgen receptor and sirtuin activity. Regarding treatment for testosterone deficiency, testosterone replacement therapy is the gold standard for the management of testosterone-deficient patients, and it improves three domains of testosterone deficiency symptoms, such as the physical, psychological and sexual domain. Recent reports suggested the importance of modifiable factors in the testosterone decline in addition to aging. Therefore, it might be responsible for the prevention of testosterone deficiency symptoms to maintain testosterone secretion taking account of the modifiable factors. The present article reviews the literature, and introduces contemporary perspectives and management of testosterone deficiency.

  4. Testosterone therapy in men with testosterone deficiency: Are we beyond the point of no return?

    PubMed Central

    2016-01-01

    Although testosterone therapy in men with testosterone deficiency was introduced in the early 1940s, utilization of this effective treatment approach in hypogonadal men is met with considerable skepticism and resistance. Indeed, for decades, the fear that testosterone may cause prostate cancer has hampered clinical progress in this field. Nevertheless, even after considerable knowledge was acquired that this fear is unsubstantiated, many in the medical community remain hesitant to utilize this therapeutic approach to treat men with hypogonadism. As the fears concerning prostate cancer have subsided, a new controversy regarding use of testosterone therapy and increase in cardiovascular disease was introduced. Although the new controversy was based on one ill-fated clinical trial, one meta-analysis with studies that utilized unapproved formulation in men with liver cirrhosis, and two retrospective studies with suspect or nonvalidated statistical methodologies and database contaminations, the flames of such controversy were fanned by the lay press and academics alike. In this review we discuss the adverse effect of testosterone deficiency and highlight the numerous proven benefits of testosterone therapy on men's health and debunk the myth that testosterone therapy increases cardiovascular risk. Ultimately, we believe that there is considerable scientific and clinical evidence to suggest that testosterone therapy is safe and effective with restoration of physiological levels in men with testosterone deficiency, irrespective of its etiology. PMID:27847912

  5. Testosterone-mediated increase in 5 alpha-dihydrotestosterone content, nuclear androgen receptor levels, and cell division in an androgen-independent prostate carcinoma of Noble rats.

    PubMed

    Ho, S M; Leav, I; Damassa, D; Kwan, P W; Merk, F B; Seto, H S

    1988-02-01

    An androgen-independent, transplantable prostate carcinoma line (AIT), originally derived from the dorsolateral prostate (DLP) of Noble rat, was implanted into orchiectomized Noble rats and its response to androgen stimulation was studied and compared to that of the regenerating DLP tissue in sexually ablated rats. AIT tumors carried in castrated hosts displayed a high basal level of proliferative activity (mitotic index (MI), 15.0 +/- 0.5) while DLP tissue in untreated castrates exhibited no proliferative activity. Following androgen stimulation by testosterone capsule implantation into host rats, the AIT responded with a marked increase in cell proliferation; MI values doubled to 30.0 +/- 2.9 on Day 5 following androgen stimulation. This androgen-induced increase in MI values was coincident with elevations in nuclear androgen receptor (20-fold increase) and 5 alpha-dihydrotestosterone content (3-fold increase) in the tumor. However, by Day 10 following androgen treatment, indices of cell proliferation in the AIT declined to pre-androgen-stimulated levels (MI, 14.8 +/- 1.9) despite the continued elevations in nuclear androgen receptor and tissue 5 alpha-dihydrotestosterone contents. Parallel changes in MI were also observed in the normal regenerating DLP following androgen stimulation. MI values in this tissue increased from nondetectable levels to 38.1 +/- 4.7 on Day 5 but declined to relatively low levels (4.5 +/- 0.9) by Day 10 following androgen replacement. Taken together these findings led us to conclude that the AIT carried in castrates is capable of responding to testosterone in a manner similar to that observed for androgen-stimulated DLP of sexually ablated rats. Thus, in both the neoplastic and regenerating tissues, the initial response to androgen is characterized by a marked enhancement of cell proliferation which was correlated with an increase in androgen receptor and 5 alpha-dihydrotestosterone content. However, like its tissue of origin, the AIT

  6. Testosterone and aggressive behavior in man.

    PubMed

    Batrinos, Menelaos L

    2012-01-01

    Atavistic residues of aggressive behavior prevailing in animal life, determined by testosterone, remain attenuated in man and suppressed through familial and social inhibitions. However, it still manifests itself in various intensities and forms from; thoughts, anger, verbal aggressiveness, competition, dominance behavior, to physical violence. Testosterone plays a significant role in the arousal of these behavioral manifestations in the brain centers involved in aggression and on the development of the muscular system that enables their realization. There is evidence that testosterone levels are higher in individuals with aggressive behavior, such as prisoners who have committed violent crimes. Several field studies have also shown that testosterone levels increase during the aggressive phases of sports games. In more sensitive laboratory paradigms, it has been observed that participant's testosterone rises in the winners of; competitions, dominance trials or in confrontations with factitious opponents. Aggressive behavior arises in the brain through interplay between subcortical structures in the amygdala and the hypothalamus in which emotions are born and the prefrontal cognitive centers where emotions are perceived and controlled. The action of testosterone on the brain begins in the embryonic stage. Earlier in development at the DNA level, the number of CAG repeats in the androgen receptor gene seems to play a role in the expression of aggressive behavior. Neuroimaging techniques in adult males have shown that testosterone activates the amygdala enhancing its emotional activity and its resistance to prefrontal restraining control. This effect is opposed by the action of cortisol which facilitates prefrontal area cognitive control on impulsive tendencies aroused in the subcortical structures. The degree of impulsivity is regulated by serotonin inhibiting receptors, and with the intervention of this neurotransmitter the major agents of the neuroendocrine

  7. Testosterone and Social Behavior

    ERIC Educational Resources Information Center

    Booth, Alan; Granger, Douglas A.; Mazur, Allan; Kivlighan, Katie T.

    2006-01-01

    Popular perceptions of the effect of testosterone on "manly" behavior are inaccurate. We need to move away from such simplistic notions by treating testosterone as one component along with other physiological, psychological and sociological variables in interactive and reciprocal models of behavior. Several hormones can now be measured in saliva,…

  8. Erythrocyte fatty acid composition does not influence levels of free, bioavailable, and total 25-hydroxy vitamin D.

    PubMed

    Carlsson, Martin; Nilsson, Ingela; Brudin, Lars; Von, Siv-Ping; Wanby, Pär

    2017-02-01

    In vitro, mono- and polyunsaturated fatty acids (FAs) may decrease the binding affinity of vitamin D metabolites for vitamin D-binding protein, which in turn may influence their bioavailability. FAs incorporated as phospholipids in erythrocyte (ery-) cell membranes reflect dietary intake. The purpose of this study was to investigate ery-FA composition in relation to markers for vitamin D. In healthy females (age 22.6 ± 2.0 years) total 25(OH)D was measured by LC-MS/MS (n = 78), free 25(OH)D with ELISA (n = 64 of 78), and bioavailable 25(OH)D was calculated. Analysis of ery-FA composition was by gas chromatography (n = 56 of 78). A strong correlation between total 25(OH)D and free 25(OH)D was seen (r = .66, p < .001), and between total-25(OH)D and bioavailable 25(OH)D (r = .68, p < .001). No correlations between 25(OH)D fractions and specific fatty acids were found, and in particular, no associations with mono- and poly-unsaturated FA compositions. All 25(OH)D fractions were correlated with leptin (total 25(OH)D (r = -.33, p < .003); bioavailable 25(OH)D (r = -.47, p < .001); free 25(OH)D (r = -.44, p < .001). Associations were found between PTH and total 25(OH)D (r = -.35, p = .002) and weaker between bioavailable 25(OH)D (r = -.35, p = .040) and free 25(OH)D (r = -.28, p = .079). All fractions of 25(OH)D appear to correlate in a similar way to PTH, BMI and body fat (leptin). No association was found between ery-FA composition and free/bioavailable 25(OH)D. It is unlikely that FAs are a strong uncoupling factor of DBP-bound 25(OH)D.

  9. Cerebral laterality for language is related to adult salivary testosterone levels but not digit ratio (2D:4D) in men: A functional transcranial Doppler ultrasound study.

    PubMed

    Papadatou-Pastou, Marietta; Martin, Maryanne

    2017-03-01

    The adequacy of three competing theories of hormonal effects on cerebral laterality are compared using functional transcranial Doppler sonography (fTCD). Thirty-three adult males participated in the study (21 left-handers). Cerebral lateralization was measured by fTCD using an extensively validated word generation task. Adult salivary testosterone (T) and cortisol (C) concentrations were measured by luminescence immunoassay and prenatal T exposure was indirectly estimated by the somatic marker of 2nd to 4th digit length ratio (2D:4D). A significant quadratic relationship between degree of cerebral laterality for language and adult T concentrations was observed, with enhanced T levels for strong left hemisphere dominance and strong right hemisphere dominance. No systematic effects on laterality were found for cortisol or 2D:4D. Findings suggest that higher levels of T are associated with a relatively attenuated degree of interhemispheric sharing of linguistic information, providing support for the callosal and the sexual differentiation hypotheses rather than the Geschwind, Behan and Galaburda (GBG) hypothesis.

  10. Effects of Testosterone Treatment in Older Men

    PubMed Central

    Snyder, P.J.; Bhasin, S.; Cunningham, G.R.; Matsumoto, A.M.; Stephens-Shields, A.J.; Cauley, J.A.; Gill, T.M.; Barrett-Connor, E.; Swerdloff, R.S.; Wang, C.; Ensrud, K.E.; Lewis, C.E.; Farrar, J.T.; Cella, D.; Rosen, R.C.; Pahor, M.; Crandall, J.P.; Molitch, M.E.; Cifelli, D.; Dougar, D.; Fluharty, L.; Resnick, S.M.; Storer, T.W.; Anton, S.; Basaria, S.; Diem, S.J.; Hou, X.; Mohler, E.R.; Parsons, J.K.; Wenger, N.K.; Zeldow, B.; Landis, J.R.; Ellenberg, S.S.

    2016-01-01

    BACKGROUND Serum testosterone concentrations decrease as men age, but benefits of raising testosterone levels in older men have not been established. METHODS We assigned 790 men 65 years of age or older with a serum testosterone concentration of less than 275 ng per deciliter and symptoms suggesting hypoandrogenism to receive either testosterone gel or placebo gel for 1 year. Each man participated in one or more of three trials — the Sexual Function Trial, the Physical Function Trial, and the Vitality Trial. The primary outcome of each of the individual trials was also evaluated in all participants. RESULTS Testosterone treatment increased serum testosterone levels to the mid-normal range for men 19 to 40 years of age. The increase in testosterone levels was associated with significantly increased sexual activity, as assessed by the Psychosexual Daily Questionnaire (P<0.001), as well as significantly increased sexual desire and erectile function. The percentage of men who had an increase of at least 50 m in the 6-minute walking distance did not differ significantly between the two study groups in the Physical Function Trial but did differ significantly when men in all three trials were included (20.5% of men who received testosterone vs. 12.6% of men who received placebo, P=0.003). Testosterone had no significant benefit with respect to vitality, as assessed by the Functional Assessment of Chronic Illness Therapy–Fatigue scale, but men who received testosterone reported slightly better mood and lower severity of depressive symptoms than those who received placebo. The rates of adverse events were similar in the two groups. CONCLUSIONS In symptomatic men 65 years of age or older, raising testosterone concentrations for 1 year from moderately low to the mid-normal range for men 19 to 40 years of age had a moderate benefit with respect to sexual function and some benefit with respect to mood and depressive symptoms but no benefit with respect to vitality or

  11. Testosterone and reproductive effort in male primates.

    PubMed

    Muller, Martin N

    2016-09-08

    Considerable evidence suggests that the steroid hormone testosterone mediates major life-history trade-offs in vertebrates, promoting mating effort at the expense of parenting effort or survival. Observations from a range of wild primates support the "Challenge Hypothesis," which posits that variation in male testosterone is more closely associated with aggressive mating competition than with reproductive physiology. In both seasonally and non-seasonally breeding species, males increase testosterone production primarily when competing for fecund females. In species where males compete to maintain long-term access to females, testosterone increases when males are threatened with losing access to females, rather than during mating periods. And when male status is linked to mating success, and dependent on aggression, high-ranking males normally maintain higher testosterone levels than subordinates, particularly when dominance hierarchies are unstable. Trade-offs between parenting effort and mating effort appear to be weak in most primates, because direct investment in the form of infant transport and provisioning is rare. Instead, infant protection is the primary form of paternal investment in the order. Testosterone does not inhibit this form of investment, which relies on male aggression. Testosterone has a wide range of effects in primates that plausibly function to support male competitive behavior. These include psychological effects related to dominance striving, analgesic effects, and effects on the development and maintenance of the armaments and adornments that males employ in mating competition.

  12. ALPK1 affects testosterone mediated regulation of proinflammatory cytokines production.

    PubMed

    Kuo, Tzer-Min; Yeh, Kun-Tu; Hsu, Hui-Ting; Chiang, Shang-Lun; Chang, Jan-Gowth; Huang, Chung-Ming; Tu, Hung-Pin; Liu, Chiu-Shong; Ko, Ying-Chin

    2015-11-01

    Alpha-protein kinase 1, also known as alpha-kinase 1 (ALPK1), is associated with chronic kidney disease (CKD), myocardial infarction, gout and type 2 diabetes mellitus (DM). In addition to having an inductive effect on the proinflammatory cytokines in monocytic THP1 cells, ALPK1 is expressed abundantly in the mouse testes. Low testosterone levels are commonly associated with arthritis, CKD, type 2 DM, cardiovascular disease and inflammation. The testosterone's anti-inflammatory effect has been demonstrated to reduce proinflammatory cytokines and adhesion molecules. In this study, we found that ALPK1 transgenic mice showed lower levels of testosterone in both the testes and the serum. Decreasing endogenous ALPK1 enhanced testosterone levels and transcripts of testosterone-regulated genes (P450scc, 3beta-HSD, P450C17, 17beta-HSD, StAR, and INSL3) in TM3 Leydig cells. In contrast, increasing testosterone decreased ALPK1 in both TM3 and monocytic THP1 cells. This decrease was accompanied by a reduction of the proinflammatory cytokines. Increased ALPK1 levels attenuated the testosterone effects in THP1 cells. Finally, we also found that ALPK1 increased the release of TNF-alpha and TGF-beta1 in the human embryonic kidney 293 cells, while testosterone inhibited ALPK1 in the primary kidney cells. Taken together, this data suggests that the balance between ALPK1 and testosterone plays a critical role in the testosterone-mediated inhibition of proinflammatory cytokines.

  13. Testosterone/estradiol ratio, is it useful in the diagnosis of erectile dysfunction and low sexual desire?

    PubMed

    Castelló-Porcar, A M; Martínez-Jabaloyas, J M

    2016-12-01

    Erectile dysfunction and low sexual desire are multifactorial diseases. The decrease in testosterone levels is one of the causes, but the effect of estradiol is not well known. Moreover, study has shown that the testosterone/estradiol ratio has more influence over sexuality than does estradiol alone. The aim of the study was to determine whether the balance between testosterone and estradiol has any relation to some aspects of sexual function. It was an ambispective study of 230 patients with urological problems unrelated to sexuality. They underwent a detailed history and hormone study including total, free, bioavailable testosterone and estradiol. They completed the Sexual Health Inventory for Men and questions 11 and 12 of the IIEF15 were used to assess impairment in sexual desire. The T/E ratio was calculated, and the relationship between the different parameters and erectile function and sexual desire were studied by univariate and multivariate analysis. The mean age was 66.32 ± 8.17 years. The percentage of patients with erectile dysfunction was 60.9% (7% severe, 14.3% moderate, 12.6% mild to moderate and 27% mild) and decreased sexual desire was 46.5%. Age, free and biodisponible testosteron were the only variables with a positive linear association with erectile dysfunction and decreased sexual desire. Age was the only independent variable for both, erectile dysfunction and sexual desire, in the multiple linear regression. There was no association between a testosterone/estradiol imbalance and an alteration in erectile function and sexual desire. Consequently, in the clinical study of these patients, it is not necessary to request estradiol in the laboratory analyses.

  14. Effects of dutasteride on serum free-testosterone and clinical significance of testosterone changes.

    PubMed

    Enatsu, N; Miyake, H; Haraguchi, T; Chiba, K; Fujisawa, M

    2016-12-01

    Sixty-two patients with benign prostate hyperplasia (BPH) who were being treated with dutasteride participated in this study. Prostate volume, uroflowmetry, blood tests, the International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF-5) were determined before and 1, 3 and 12 months after the treatment with dutasteride. Patients were divided into two groups based on changes in serum testosterone after 1 month: Group A (>20% increase; n = 33) or Group B (<20% increase; n = 29). Serum free-testosterone levels were 20.4% higher after 1 month and remained constant thereafter. When Groups A and B were compared, baseline free-testosterone levels were significantly lower in Group A, IPSS QOL was significantly better in Group A at 3 and 12 months, and no significant differences were observed in uroflowmetry, prostate volume, IPSS or IIEF-5. A univariate analysis identified serum free-testosterone levels and the IPSS storage symptom subscore as significant factors influencing IPSS QOL at 12 months, and only the IPSS storage symptom subscore appeared to be independently related to IPSS QOL. These results indicate that dutasteride increases serum free-testosterone levels in BPH patients, particularly with low baseline free-testosterone levels, and the increase in free-testosterone may have further add-on impacts on their urinary tract symptoms.

  15. Sex Hormone Binding Globulin Modifies Testosterone Action and Metabolism in Prostate Cancer Cells.

    PubMed

    Li, Huika; Pham, Thy; McWhinney, Brett C; Ungerer, Jacobus P; Pretorius, Carel J; Richard, Derek J; Mortimer, Robin H; d'Emden, Michael C; Richard, Kerry

    2016-01-01

    Sex Hormone Binding Globulin (SHBG) is the major serum carrier of sex hormones. However, growing evidence suggests that SHBG is internalised and plays a role in regulating intracellular hormone action. This study was to determine whether SHBG plays a role in testosterone uptake, metabolism, and action in the androgen sensitive LNCaP prostate cancer cell line. Internalisation of SHBG and testosterone, the effects of SHBG on testosterone uptake, metabolism, regulation of androgen responsive genes, and cell growth were assessed. LNCaP cells internalised SHBG by a testosterone independent process. Testosterone was rapidly taken up and effluxed as testosterone-glucuronide; however this effect was reduced by the presence of SHBG. Addition of SHBG, rather than reducing testosterone bioavailability, further increased testosterone-induced expression of prostate specific antigen and enhanced testosterone-induced reduction of androgen receptor mRNA expression. Following 38 hours of testosterone treatment cell morphology changed and growth declined; however, cotreatment with SHBG abrogated these inhibitory effects. These findings clearly demonstrate that internalised SHBG plays an important regulatory and intracellular role in modifying testosterone action and this has important implications for the role of SHBG in health and disease.

  16. Sex Hormone Binding Globulin Modifies Testosterone Action and Metabolism in Prostate Cancer Cells

    PubMed Central

    Li, Huika; Ungerer, Jacobus P.; Pretorius, Carel J.; Mortimer, Robin H.; d'Emden, Michael C.

    2016-01-01

    Sex Hormone Binding Globulin (SHBG) is the major serum carrier of sex hormones. However, growing evidence suggests that SHBG is internalised and plays a role in regulating intracellular hormone action. This study was to determine whether SHBG plays a role in testosterone uptake, metabolism, and action in the androgen sensitive LNCaP prostate cancer cell line. Internalisation of SHBG and testosterone, the effects of SHBG on testosterone uptake, metabolism, regulation of androgen responsive genes, and cell growth were assessed. LNCaP cells internalised SHBG by a testosterone independent process. Testosterone was rapidly taken up and effluxed as testosterone-glucuronide; however this effect was reduced by the presence of SHBG. Addition of SHBG, rather than reducing testosterone bioavailability, further increased testosterone-induced expression of prostate specific antigen and enhanced testosterone-induced reduction of androgen receptor mRNA expression. Following 38 hours of testosterone treatment cell morphology changed and growth declined; however, cotreatment with SHBG abrogated these inhibitory effects. These findings clearly demonstrate that internalised SHBG plays an important regulatory and intracellular role in modifying testosterone action and this has important implications for the role of SHBG in health and disease. PMID:27990161

  17. A Giant Ovarian Cyst in a Neonate with Classical 21-Hydroxylase Deficiency with Very High Testosterone Levels Demonstrating a High-Dose Hook Effect

    PubMed Central

    Güran, Tülay; Yeşil, Gözde; Güran, Ömer; Cesur, Suna; Bosnalı, Oktav; Celayir, Ayşenur; Topçuoğlu, Sevilay; Bereket, Abdullah

    2012-01-01

    Congenital adrenal hyperplasia (CAH) is a group of disorders affecting the adrenal steroid synthesis. The most common form, 21-hydroxylase deficiency (21-OHD), leads to decreased production of cortisol and aldosterone with increased androgen secretion. In classic CAH, glucocorticoid treatment can be life-saving and serves to bring the symptoms under control. However, the treatment challenge is to effectively control the excess androgen effect by using the lowest possible glucocorticoid dose. Previous studies suggested a relationship between ovarian cyst formation and adrenal androgen excess, but neonatal large ovarian cysts have been very rarely reported in newborns with CAH. Here, we present the unique case of a neonate with classical 21-OHD who underwent surgery for a giant (10x8x7 cm) unilateral solitary ovarian follicular cyst on the 2nd postnatal day. Hormonal evaluation of the patient revealed high-dose hook effect for serum testosterone levels for the first time by a two-site immunoradiometric assay. Possible mechanisms by which androgen excess may cause ovarian cyst formation are discussed. Conflict of interest:None declared. PMID:22664361

  18. A glyphosate-based herbicide induces necrosis and apoptosis in mature rat testicular cells in vitro, and testosterone decrease at lower levels.

    PubMed

    Clair, Emilie; Mesnage, Robin; Travert, Carine; Séralini, Gilles-Éric

    2012-03-01

    The major herbicide used worldwide, Roundup, is a glyphosate-based pesticide with adjuvants. Glyphosate, its active ingredient in plants and its main metabolite (AMPA) are among the first contaminants of surface waters. Roundup is being used increasingly in particular on genetically modified plants grown for food and feed that contain its residues. Here we tested glyphosate and its formulation on mature rat fresh testicular cells from 1 to 10000ppm, thus from the range in some human urine and in environment to agricultural levels. We show that from 1 to 48h of Roundup exposure Leydig cells are damaged. Within 24-48h this formulation is also toxic on the other cells, mainly by necrosis, by contrast to glyphosate alone which is essentially toxic on Sertoli cells. Later, it also induces apoptosis at higher doses in germ cells and in Sertoli/germ cells co-cultures. At lower non toxic concentrations of Roundup and glyphosate (1ppm), the main endocrine disruption is a testosterone decrease by 35%. The pesticide has thus an endocrine impact at very low environmental doses, but only a high contamination appears to provoke an acute rat testicular toxicity. This does not anticipate the chronic toxicity which is insufficiently tested, and only with glyphosate in regulatory tests.

  19. Effects of climate on the thermoregulatory responses of male buffalo ( Bubalus-bubalis) calves supplemented with different levels of testosterone and TDN

    NASA Astrophysics Data System (ADS)

    Gangwar, P. C.

    1982-03-01

    The present work was undertaken to study the changes in the thermoregulatory responses due to changing climate, androgen and TDN percent in 12 buffalo male calves from 4 months of age for a period of two years. The results obtained were: (1) The amplitudes of the diurnal cycles in rectal temperature (Tre) in each month of the experiment were very similar but longer in summer months as compared to winter months, (2) The correlation between Tre and ambient temperature (Ta) was high in all months. (3) Buffalo calves without testosterone supplementation on 70% TDN showed maximum rise in Tre by 0.076 0‡C per degree of ambient temperature, indicating more strain, (4) Highest respiratory frequencies occurred at 10:00 h during summer months. Subgroup 2 of group 1 showed the maximum rise by 311% in respiratory frequency in summer over winter due to least acclimatization, (5) The mean daily increase by 9.94‡C in ambient temperature doubled the respiratory frequency of male buffalo calves from January to April, and (6) Androgen therapy and higher TDN percent level helped the male buffalo calves to adjust better and sooner than the other calves to changing climates.

  20. Changes in plasma testosterone levels and brain AVT cell number during the breeding season in the green treefrog.

    PubMed

    O'Bryant, Erin L; Wilczynski, Walter

    2010-01-01

    We exposed groups of adult male green treefrogs, Hyla cinerea, to acoustic stimuli (natural chorus or random tones) for seven consecutive nights at three time points during their natural breeding season (May, July, and September) and assessed seasonal changes in plasma androgen levels and number of arginine vasotocin (AVT) immunoreactive cells in the brain over this time period. We also tested whether social cues altered either androgens or AVT-ir cell number or size at each time point. Finally, we analyzed how these factors related to calling behavior. Data were collected over two breeding seasons. Call rate (calls/h) was assessed during the stimulus time (i.e. 'evoked calling') and during the remainder of the day ('spontaneous calling'). Plasma hormone levels were measured at the end of the acoustic treatment when brains were collected for immunocytochemistry. Circulating androgen levels declined over the breeding season. Males exposed to chorus sounds, however, had higher androgen levels than males exposed to tones. AVT-ir cell number increased across the breeding season in the nucleus accumbens but not the amygdala, anterior preoptic area, or magnocellular preoptic area, and soma size decreased in the nucleus accumbens as cell number increased. Social stimulation had no significant influence on either AVT-ir cell measure. Evoked call rate was higher in males exposed to natural chorus sounds compared to those exposed to random tones, but did not change during the season. In contrast, spontaneous call rate was higher at the beginning of the breeding season compared to the end, and unlike evoked calling was correlated with circulating androgen levels across all treatments and time points. AVT-ir soma size was positively correlated with both evoked and spontaneous calling. These results suggest that social exposure can prolong the elevation of gonadal hormones in the bloodstream, thus mitigating or slowing the seasonal decline of such hormones. In contrast, social

  1. Diagnosis and management of testosterone deficiency.

    PubMed

    McBride, James A; Carson, Culley C; Coward, Robert M

    2015-01-01

    Testosterone supplementation therapy (TST) use has dramatically increased over the past decade, due to the availability of newer agents, aggressive marketing, and an increasing incidence of testosterone deficiency (TD). Despite the increase in TST, a degree of ambiguity remains as to the exact diagnostic criteria of TD, and administration and monitoring of TST. One explanation for this phenomenon is the complex role testosterone plays in multiple physiologic pathways. Numerous medical co-morbidities and medications can alter testosterone levels resulting in a wide range of nonspecific clinical signs and symptoms of TD. The diagnosis is also challenging due to the lack of a definitive serum total testosterone level that reliably correlates with symptoms. This observation is particularly true in the aging male and is exacerbated by inconsistencies between different laboratory assays. Several prominent medical societies have developed guideline statements to clarify the diagnosis, but they differ from each other and with expert opinion in several ways. Aside from diagnostic dilemmas, there are numerous subtle advantages and disadvantages of the various testosterone agents to appreciate. The available TST agents have changed significantly over the past decade similar to the trends in the diagnosis of TD. Therefore, as the usage of TST increases, clinicians will be challenged to maintain an up-to-date understanding of TD and TST. The purpose of this review is to provide a clear description of the current strategies for diagnosis and management of TD.

  2. Diagnosis and management of testosterone deficiency

    PubMed Central

    McBride, James A; Carson, Culley C; Coward, Robert M

    2015-01-01

    Testosterone supplementation therapy (TST) use has dramatically increased over the past decade, due to the availability of newer agents, aggressive marketing, and an increasing incidence of testosterone deficiency (TD). Despite the increase in TST, a degree of ambiguity remains as to the exact diagnostic criteria of TD, and administration and monitoring of TST. One explanation for this phenomenon is the complex role testosterone plays in multiple physiologic pathways. Numerous medical co-morbidities and medications can alter testosterone levels resulting in a wide range of nonspecific clinical signs and symptoms of TD. The diagnosis is also challenging due to the lack of a definitive serum total testosterone level that reliably correlates with symptoms. This observation is particularly true in the aging male and is exacerbated by inconsistencies between different laboratory assays. Several prominent medical societies have developed guideline statements to clarify the diagnosis, but they differ from each other and with expert opinion in several ways. Aside from diagnostic dilemmas, there are numerous subtle advantages and disadvantages of the various testosterone agents to appreciate. The available TST agents have changed significantly over the past decade similar to the trends in the diagnosis of TD. Therefore, as the usage of TST increases, clinicians will be challenged to maintain an up-to-date understanding of TD and TST. The purpose of this review is to provide a clear description of the current strategies for diagnosis and management of TD. PMID:25532575

  3. Testosterone, thrombophilia, and thrombosis.

    PubMed

    Glueck, Charles J; Richardson-Royer, Caitlin; Schultz, Reiker; Burger, Tim; Labitue, Fanta; Riaz, Muhammad K; Padda, Jagjit; Bowe, Dedrick; Goldenberg, Naila; Wang, Ping

    2014-01-01

    We describe thrombosis, deep venous thrombosis (DVT) pulmonary embolism (PE; n = 9) and hip-knee osteonecrosis (n = 5) that developed after testosterone therapy (median 11 months) in 14 previously healthy patients (13 men and 1 woman; 13 Caucasian and 1 African American), with no antecedent thrombosis and previously undiagnosed thrombophilia-hypofibrinolysis. Of the 14 patients, 3 were found to be factor V Leiden heterozygotes, 3 had high factor VIII, 3 had plasminogen activator inhibitor 1 4G4G homozygosity, 2 had high factor XI, 2 had high homocysteine, 1 had low antithrombin III, 1 had the lupus anticoagulant, 1 had high anticardiolipin antibody Immunoglobulin G, and 1 had no clotting abnormalities. In 4 men with thrombophilia, DVT-PE recurred when testosterone was continued despite therapeutic international normalized ratio on warfarin. In 60 men on testosterone, 20 (33%) had high estradiol (E2 >42.6 pg/mL). When exogenous testosterone is aromatized to E2, and E2-induced thrombophilia is superimposed on thrombophilia-hypofibrinolysis, thrombosis occurs. The DVT-PE and osteonecrosis after starting testosterone are associated with previously undiagnosed thrombophilia-hypofibrinolysis. Thrombophilia should be ruled out before administration of exogenous testosterone.

  4. Effects of testosterone and resistance training in men with chronic obstructive pulmonary disease.

    PubMed

    Casaburi, Richard; Bhasin, Shalender; Cosentino, Louis; Porszasz, Janos; Somfay, Attila; Lewis, Michael I; Fournier, Mario; Storer, Thomas W

    2004-10-15

    Dysfunction of the muscles of ambulation contributes to exercise intolerance in chronic obstructive pulmonary disease (COPD). Men with COPD have high prevalence of low testosterone levels, which may contribute to muscle weakness. We determined effects of testosterone supplementation (100 mg of testosterone enanthate injected weekly) with or without resistance training (45 minutes three times weekly) on body composition and muscle function in 47 men with COPD (mean FEV(1) = 40% predicted) and low testosterone levels (mean = 320 ng/dl). Subjects were randomized to 10 weeks of placebo injections + no training, testosterone injections + no training, placebo injections + resistance training, or testosterone injections + resistance training. Testosterone injections yielded a mean increase of 271 ng/dl in the nadir serum testosterone concentration (to the middle of the normal range for young men). The lean body mass (by dual-energy X-ray absorptiometry) increase averaged 2.3 kg with testosterone alone and 3.3 kg with combined testosterone and resistance training (p < 0.001). Increase in one-repetition maximum leg press strength averaged 17.2% with testosterone alone, 17.4% with resistance training alone, and 26.8% with testosterone + resistance training (p < 0.001). Interventions were well tolerated with no abnormalities in safety measures. Further studies are required to determine long-term benefits of adding testosterone supplementation and resistance training to rehabilitative programs for carefully screened men with COPD and low testosterone levels.

  5. Effect of finasteride on serum levels of androstenedione, testosterone and their 5α-reduced metabolites in men at risk for prostate cancer.

    PubMed

    Stanczyk, Frank Z; Azen, Colleen G; Pike, Malcolm C

    2013-11-01

    Studies show that treatment of men with 5α-reductase inhibitors such as finasteride is effective for the primary prevention of prostate cancer. Although it is known that finasteride treatment suppresses serum levels of dihydrotestosterone (DHT) and its distal metabolite, 5α-androstane-3α,17β-diol glucuronide (3α-diol G), and increases serum testosterone (T) levels, little is known about its effect on other precursors and metabolites of DHT, as well as on the relationship of these androgens to prostate specific antigen (PSA), a marker of prostatic intraepithelial neoplasia. The present study provides new data on the effect of finasteride on precursors and metabolites of DHT. Fifty-three men, ages 57-79 years, with elevated PSA levels (>4ng/ml), were randomized to treatment with finasteride (5mg/day) or observation (controls) for 12 months. Blood samples were obtained at baseline, 1, 3, 6 and 12 months for measurement of PSA, androstenedione (A), T, DHT, 3α-diol G, androsterone glucuronide (ADT G) and DHT sulfate (DHT S) in serum by validated, highly specific radioimmunoassays. Statistical analysis was carried out using mixed model ANOVA and t-tests. In the control group, PSA and androgen levels were unchanged throughout the 12 months of treatment. In the finasteride group, PSA, DHT, DHT S, 3α-diol G and ADT G decreased from baseline to 1 month by 23.2%, 78.7%, 71.0%, 75.7% and 43.0%, respectively. The change in PSA decreased further to 46.1% and 55.1% at 3 and 12 months of treatment, respectively, whereas the decrease in androgens observed at 1 month did not change by more than 6.9% for DHT, DHT S and 3α-diol G in the subsequent months of sampling. However, the decline in ADT G was only 22.2% at month 3, and remained essentially at this level after that time. In contrast, T and A increased significantly from baseline, and the increase in A of approximately 34.5% was about 1.9 times the increase in T (approximately 18.3%). The present data suggest that either

  6. Cognitive effects of testosterone and finasteride administration in older hypogonadal men

    PubMed Central

    Borst, Stephen E; Yarrow, Joshua F; Fernandez, Carmen; Conover, Christine F; Ye, Fan; Meuleman, John R; Morrow, Matthew; Zou, Baiming; Shuster, Jonathan J

    2014-01-01

    Serum concentrations of neuroactive androgens decline in older men and, in some studies, low testosterone is associated with decreased cognitive function and incidence of depression. Existing studies evaluating the effect of testosterone administration on cognition in older men have been largely inconclusive, with some studies reporting minor to moderate cognitive benefit, while others indicate no cognitive effect. Our objective was to assess the cognitive effects of treating older hypogonadal men for 1 year with a supraphysiological dose of testosterone, either alone or in combination with finasteride (a type II 5α-reductase inhibitor), in order to determine whether testosterone produces cognitive benefit and whether suppressed dihydrotestosterone influences cognition. Sixty men aged ≥60 years with a serum testosterone concentration of ≤300 ng/dL or bioavailable testosterone ≤70 ng/dL and no evidence of cognitive impairment received testosterone-enanthate (125 mg/week) versus vehicle, paired with finasteride (5 mg/day) versus placebo using a 2×2 factorial design. Testosterone caused a small decrease in depressive symptoms as assessed by the Geriatric Depression Scale and a moderate increase in visuospatial memory as assessed by performance on a recall trial of the Rey-Osterrieth Complex Figure Test. Finasteride caused a small increase in performance on the Benton Judgment of Line Orientation test. In total, major improvements in cognition were not observed either with testosterone or finasteride. Further studies are warranted to determine if testosterone replacement may improve cognition in other domains. PMID:25143719

  7. Cognitive effects of testosterone and finasteride administration in older hypogonadal men.

    PubMed

    Borst, Stephen E; Yarrow, Joshua F; Fernandez, Carmen; Conover, Christine F; Ye, Fan; Meuleman, John R; Morrow, Matthew; Zou, Baiming; Shuster, Jonathan J

    2014-01-01

    Serum concentrations of neuroactive androgens decline in older men and, in some studies, low testosterone is associated with decreased cognitive function and incidence of depression. Existing studies evaluating the effect of testosterone administration on cognition in older men have been largely inconclusive, with some studies reporting minor to moderate cognitive benefit, while others indicate no cognitive effect. Our objective was to assess the cognitive effects of treating older hypogonadal men for 1 year with a supraphysiological dose of testosterone, either alone or in combination with finasteride (a type II 5α-reductase inhibitor), in order to determine whether testosterone produces cognitive benefit and whether suppressed dihydrotestosterone influences cognition. Sixty men aged ≥ 60 years with a serum testosterone concentration of ≤ 300 ng/dL or bioavailable testosterone ≤ 70 ng/dL and no evidence of cognitive impairment received testosterone-enanthate (125 mg/week) versus vehicle, paired with finasteride (5 mg/day) versus placebo using a 2×2 factorial design. Testosterone caused a small decrease in depressive symptoms as assessed by the Geriatric Depression Scale and a moderate increase in visuospatial memory as assessed by performance on a recall trial of the Rey-Osterrieth Complex Figure Test. Finasteride caused a small increase in performance on the Benton Judgment of Line Orientation test. In total, major improvements in cognition were not observed either with testosterone or finasteride. Further studies are warranted to determine if testosterone replacement may improve cognition in other domains.

  8. Effects of gendered behavior on testosterone in women and men

    PubMed Central

    van Anders, Sari M.; Steiger, Jeffrey; Goldey, Katherine L.

    2015-01-01

    Testosterone is typically understood to contribute to maleness and masculinity, although it also responds to behaviors such as competition. Competition is crucial to evolution and may increase testosterone but also is selectively discouraged for women and encouraged for men via gender norms. We conducted an experiment to test how gender norms might modulate testosterone as mediated by two possible gender→testosterone pathways. Using a novel experimental design, participants (trained actors) performed a specific type of competition (wielding power) in stereotypically masculine vs. feminine ways. We hypothesized in H1 (stereotyped behavior) that wielding power increases testosterone regardless of how it is performed, vs. H2 (stereotyped performance), that wielding power performed in masculine but not feminine ways increases testosterone. We found that wielding power increased testosterone in women compared with a control, regardless of whether it was performed in gender-stereotyped masculine or feminine ways. Results supported H1 over H2: stereotyped behavior but not performance modulated testosterone. These results also supported theory that competition modulates testosterone over masculinity. Our findings thus support a gender→testosterone pathway mediated by competitive behavior. Accordingly, cultural pushes for men to wield power and women to avoid doing so may partially explain, in addition to heritable factors, why testosterone levels tend to be higher in men than in women: A lifetime of gender socialization could contribute to “sex differences” in testosterone. Our experiment opens up new questions of gender→testosterone pathways, highlighting the potential of examining nature/nurture interactions and effects of socialization on human biology. PMID:26504229

  9. Effects of gendered behavior on testosterone in women and men.

    PubMed

    van Anders, Sari M; Steiger, Jeffrey; Goldey, Katherine L

    2015-11-10

    Testosterone is typically understood to contribute to maleness and masculinity, although it also responds to behaviors such as competition. Competition is crucial to evolution and may increase testosterone but also is selectively discouraged for women and encouraged for men via gender norms. We conducted an experiment to test how gender norms might modulate testosterone as mediated by two possible gender→testosterone pathways. Using a novel experimental design, participants (trained actors) performed a specific type of competition (wielding power) in stereotypically masculine vs. feminine ways. We hypothesized in H1 (stereotyped behavior) that wielding power increases testosterone regardless of how it is performed, vs. H2 (stereotyped performance), that wielding power performed in masculine but not feminine ways increases testosterone. We found that wielding power increased testosterone in women compared with a control, regardless of whether it was performed in gender-stereotyped masculine or feminine ways. Results supported H1 over H2: stereotyped behavior but not performance modulated testosterone. These results also supported theory that competition modulates testosterone over masculinity. Our findings thus support a gender→testosterone pathway mediated by competitive behavior. Accordingly, cultural pushes for men to wield power and women to avoid doing so may partially explain, in addition to heritable factors, why testosterone levels tend to be higher in men than in women: A lifetime of gender socialization could contribute to "sex differences" in testosterone. Our experiment opens up new questions of gender→testosterone pathways, highlighting the potential of examining nature/nurture interactions and effects of socialization on human biology.

  10. FETAL TESTOSTERONE LEVELS ARE DIFFERENTIALLY AFFECTED IN MALE SPRAGUE DAWLEY AND WISTAR RATS AFTER IN UTERO EXPOSURE TO DIETHYLHEXYL PHTHALATE: A DOSE RESPONSE STUDY.

    EPA Science Inventory

    Exposure to phthalate esters during sexual differentiation disrupts testosterone resulting in malformations of androgen-dependent tissues. We have found that gubernacular lesions are more prevalent in in utero diethylhexyl phthalate (DEHP)-treated Wistar male than in the SD rat o...

  11. Modulation of pain sensation by stress-related testosterone and cortisol.

    PubMed

    Choi, J C; Chung, M I; Lee, Y D

    2012-10-01

    Stress increases cortisol and decreases testosterone. It is not known whether pain is affected by stress-related testosterone. Therefore, we investigated whether stress can affect pain perception by decreasing testosterone and increasing cortisol. Pain thresholds, pain and anxiety ratings and salivary testosterone and cortisol levels were measured in 46 healthy men during resting and stressful conditions. Pain was induced by electrical stimulation. Stress was induced by having participants perform a medical test. Stress significantly increased anxiety ratings and salivary cortisol levels, but decreased salivary testosterone levels. Stress also increased pain ratings and decreased pain thresholds. During stress, cortisol levels were negatively correlated with pain thresholds and testosterone levels were positively correlated with pain thresholds. Results indicated that testosterone can decrease and cortisol can increase pain induced by electrical stimulation, suggesting that acute clinical pain may be relieved by controlling stress and managing consequent stress-related testosterone and cortisol.

  12. The Effect of Special Operations Training on Testosterone, Lean Body Mass, and Strength and the Potential for Therapeutic Testosterone Replacement: A Review of the Literature

    DTIC Science & Technology

    2016-07-01

    Testosterone Therapy Exogenous testosterone therapy has shown modest benefits in anti-aging research as well as in combating type 2 diabetes and...Alzheimer’s disease. Males typically experience reductions in testosterone as a function of aging, resulting in low levels of LBM, while type 2 diabetics

  13. Testosterone and social and reproductive behaviour in Aphelocoma jays.

    PubMed

    Vleck; Brown

    1999-11-01

    When there is a direct relationship between testosterone level and payoff in reproductive success through aggression, testosterone levels should be elevated. Elevated testosterone, however, has fitness costs, particularly a decreased tendency to display parental care. Thus the pattern of testosterone secretion in males should vary with the social and mating system. Western scrub-jays, Aphelocoma californica woodhouseii, form monogamous pairs on territories during the breeding season. Mexican jays, A. ultramarina, live in large, stable groups and up to five females within a group attempt nesting each spring. In both species, testosterone levels rose rapidly in March and peak levels did not differ. Elevated testosterone levels were only observed for about 3 weeks in the monogamous western scrub-jay, but were observed into May in Mexican jays, a reflection of prolonged opportunity for males to mate with multiple females and continual interaction with other competing males. In Mexican jays, nonbreeding yearlings had lower testosterone levels than all other age groups. Testosterone in males owning nests did not differ from that in other adult males, many of whom engage in extrapair fertilizations. Testosterone was elevated throughout the incubation phase, but was significantly lower when chicks were present in any nest in the group. Nearly all birds in the group fed all chicks. These observations support the hypothesis that testosterone is elevated when male-male competition is frequent and mating opportunities depend on the outcome of that competition, and testosterone is decreased when the necessity for parental or alloparental care would make its effects deleterious. Copyright 1999 The Association for the Study of Animal Behaviour.

  14. An open label, dose response study to determine the effect of a dietary supplement on dihydrotestosterone, testosterone and estradiol levels in healthy males

    PubMed Central

    Angwafor, Fru; Anderson, Mark L

    2008-01-01

    Background Maintaining endogenous testosterone (T) levels as men age may slow the symptoms of sarcopenia, andropause and decline in physical performance. Drugs inhibiting the enzyme 5α-reductase (5AR) produce increased blood levels of T and decreased levels of dihydrotestosterone (DHT). However, symptoms of gynecomastia have been reported due to the aromatase (AER) enzyme converting excess T to estradiol (ES). The carotenoid astaxanthin (AX) from Haematococcus pluvialis, Saw Palmetto berry lipid extract (SPLE) from Serenoa repens and the precise combination of these dietary supplements, Alphastat® (Mytosterone(™)), have been reported to have inhibitory effects on both 5AR and AER in-vitro. Concomitant regulation of both enzymes in-vivo would cause DHT and ES blood levels to decrease and T levels to increase. The purpose of this clinical study was to determine if patented Alphastat® (Mytosterone(™)) could produce these effects in a dose dependent manner. Methods To investigate this clinically, 42 healthy males ages 37 to 70 years were divided into two groups of twenty-one and dosed with either 800 mg/day or 2000 mg/day of Alphastat® (Mytosterone(™)) for fourteen days. Blood samples were collected on days 0, 3, 7 and 14 and assayed for T, DHT and ES. Body weight and blood pressure data were collected prior to blood collection. One-way, repeated measures analysis of variance (ANOVA-RM) was performed at a significance level of alpha = 0.05 to determine differences from baseline within each group. Two-way analysis of variance (ANOVA-2) was performed after baseline subtraction, at a significance level of alpha = 0.05 to determine differences between dose groups. Results are expressed as means ± SEM. Results ANOVA-RM showed significant within group increases in serum total T and significant decreases in serum DHT from baseline in both dose groups at a significance level of alpha = 0.05. Significant decreases in serum ES are reported for the 2000 mg/day dose

  15. The role of testosterone in trichloroethylene penetration in vitro

    SciTech Connect

    McCormick, K.; Abdel-Rahman, M.S. )

    1991-02-01

    Sex differences are known to exist in the metabolism and bioavailability of trichloroethylene (TCE). This study revealed that dermal penetration of ({sup 14}C)TCE in vitro was twofold greater in untreated female than in untreated male Sprague-Dawley rats. Since testosterone has been shown to mediate a wide variety of sex differences, its role in dermal penetration of ({sup 14}C)TCE was investigated. Penetration was measured by using an in vitro evaporation-penetration cell with a 10-hour collection period. Depriving male rats of testosterone (by castration) resulted in increased values for total penetration, area under the curve (AUC), and penetration slopes compared to those found in the female control group. Administration of testosterone to female animals produced values for total penetration, AUC, and penetration slopes significantly lower than those of the female control group.

  16. Testosterone replacement therapy in obese males.

    PubMed

    Drewa, Tomasz; Olszewska-Słonina, Dorota; Chlosta, Piotr

    2011-01-01

    Controversy surrounds testosterone replacement therapy in obese ageing due to no generally accepted lower limits of normal testosterone level and high prevalence of hypogonadal symptoms in the ageing male population and the non-specific nature of these symptoms. Late onset hypogonadism is a clinical and biochemical syndrome associated with advancing age, often coexisting with obesity and metabolic syndrome. High fat and carbohydrates (fructose) consumption is responsible for development of obesity and metabolic syndrome which is one of risk factors for hypogonadism in older men. High fructose intake has been shown to cause dyslipidemia and to impair hepatic insulin sensitivity. Obesity and lack of physical activity negatively influence testosterone level. Low testosterone level should be regarded as an effect of obesity, but reverse relationship has not been proved yet. The management of late-onset hypogonadism symptoms has to be treated by a change of a life style and prevented with healthy nutrition and physical activity. The question related to rational indications for testosterone replacement therapy in obese males seems to be still actual.

  17. Effect of Testosterone Replacement Therapy on Cognitive Performance and Depression in Men with Testosterone Deficiency Syndrome

    PubMed Central

    Jung, Hyun Jin

    2016-01-01

    Purpose We aimed to evaluate the effect of testosterone replacement therapy (TRT) on cognitive function and depression in men with testosterone deficiency syndrome. Materials and Methods We carried out a prospective, placebo-controlled trial involving 106 men with total testosterone levels <3.3 ng/mL and symptoms of hypogonadism. Based on whether the patients received TRT (injection with 1,000 mg testosterone undecanoate) or a placebo (advice to modify lifestyle), the study population was divided into a TRT group (n=54) and a control group (n=52). Results The age among patients in the TRT and control groups was 56.7±12.6 years and 57.8±11.4 years, respectively (p> 0.05). At baseline, no significant differences between the TRT and control groups were noted regarding serum testosterone or prostate-specific antigen levels, or regarding the scores for aging symptoms (Aging Males' Symptoms scale), erectile function (5-item International Index of Erectile Function questionnaire), cognitive function (Korean Mini-Mental State Examination), and depression (Beck Depression Inventory). At 8 months after intervention total serum testosterone levels and erectile function scores had significantly increased (p<0.05), whereas the scores for aging symptoms and depression had significantly decreased (p<0.05) in the TRT group; no significant improvement in any parameters was noted for the control group. Notably, significant improvement in cognitive function was noted among patients with cognitive impairment at baseline (cognitive function score <25) who received TRT. Conclusions TRT may be considered in men with testosterone deficiency syndrome if low testosterone levels are associated with depression or cognitive impairment. PMID:28053949

  18. Risks of testosterone replacement therapy in ageing men.

    PubMed

    Tan, R S; Salazar, J A

    2004-11-01

    Testosterone has been available to practitioners for several decades. However, testosterone prescriptions have increased in recent years partly because of the introduction of newer delivery systems that are topical and have good bioavailability. In the US alone, approximately 2 million prescriptions for testosterone were written in 2002. This represents a 30% increase from 2001 and a 170% increase from 1999. There has also been a 500% increase in prescription sales in the past 10 years. The rise in prescriptions may be in part due to the increasing recognition of hypogonadism in ageing males or andropause. Treatment relating to hypogonadism has relieved symptoms and improved the quality of life of many individuals. Epidemiological studies point toward an association with increased morbidity and mortality, with low testosterone states in ageing males. For example, there is a higher prevalence of depression, coronary heart disease, osteoporosis, fracture rates, frailty and even dementia with low testosterone states. Recently, there have been some concerns raised regarding the long-term safety of testosterone replacement therapy (TRT) from the Institute of Medicine. Current evidence suggests no causal relationship between prostate cancer and physiological dosing of testosterone, especially with careful selection and monitoring of patients. Cardiovascular risks have, overall, been neutral, although suggestions have been made that there are positive vasodilatory properties with testosterone. Mild eythrocytosis can be a common side effect of TRT, but thromboembolic events have rarely been reported in the literature. This paper addresses the evidence to date regarding the safety aspects of TRT. The medical-legal implications of TRT for men at this point in time is also discussed.

  19. Assessment of trace metals contamination level, bioavailability and toxicity in sediments from Dakar coast and Saint Louis estuary in Senegal, West Africa.

    PubMed

    Diop, Cheikh; Dewaelé, Dorothée; Cazier, Fabrice; Diouf, Amadou; Ouddane, Baghdad

    2015-11-01

    Trace metals have the potential to associate with sediments that have been recognised as significant source of contamination for the benthic environment. The current study aims assessing the trace metals contamination level in sediments from Dakar coast and Saint Louis estuary, and to examine their bioavailability to predict potential toxicity of sediments. Surface sediment samples were collected between June 2012 and January 2013 in three sampling periods from eight stations. Trace metals were analysed using inductively coupled plasma-optical emission spectrometer. Geoaccumulation indexes (Igeo) showed strong pollution by Cd, Cr, Cu and Pb confirmed by enrichment factor (EF) suggesting that these metals derived from anthropogenic sources. Toxicity indexes exceeded one in several sites suggesting the potential effects on sediment-dwelling organisms, which may constitute a risk to populations' health. However, seasonal variability of metal bioavailability was noted, revealing the best period to monitor metal contamination. From an ecotoxicological point of view, concentrations of Cd, Cr, Cu and Pb were above the effects range low threshold limit of the sediment quality guidelines for adverse biological effects. In addition, with Pb concentrations above the effect range medium values in some sites, biological effects may occur.

  20. Outcomes of long-term testosterone replacement in older hypogonadal males: a retrospective analysis.

    PubMed

    Hajjar, R R; Kaiser, F E; Morley, J E

    1997-11-01

    To determine the complications, toxicities, and compliance of long term testosterone replacement in hypogonadal males, we retrospectively assessed 45 elderly hypogonadal men receiving testosterone replacement therapy and 27 hypogonadal men taking testosterone. Hypogonadism was defined as a bioavailable testosterone serum concentration of 72 ng/dL or less. Both groups received baseline physical examinations and blood tests. The testosterone-treated group received 200 mg testosterone enanthate or cypionate im every 2 weeks, and follow-up examinations and blood samplings were performed every 3 months. The control group had a single follow-up blood test and physical examination. There was no significant difference in the initial blood tests in the two groups. At 2 yr follow-up, only the hematocrit showed a statistically significant increase in the testosterone-treated group compared to the control group (P < 0.001). A decrease in the urea nitrogen to creatinine ratio and an increase in the prostate-specific antigen concentration was not statistically significant. Eleven (24%) of the testosterone-treated subjects developed polycythemia sufficient to require phlebotomy or the temporary withholding of testosterone, one third of which occurred less than 1 yr after starting testosterone treatment. There was no significant difference in the incidence of new illness in the two groups during the 2-yr follow-up. Although self-assessment of libido was dramatically improved in the testosterone-treated group (P < 0.0001), approximately one third of the subjects discontinued therapy. In conclusion, testosterone replacement therapy appears to be well tolerated by over 84% of the subjects. Long term testosterone replacement to date appears to be a safe and effective means of treating hypogonadal elderly males, provided that frequent follow-up blood tests and examinations are performed.

  1. The long-term efficacy and safety of a testosterone mucoadhesive buccal tablet in testosterone-deficient men.

    PubMed

    Dinsmore, Wallace W; Wyllie, Michael G

    2012-07-01

    What's known on the subject? and What does the study add? Striant® SR is the only available buccal delivery system for testosterone replacement therapy. Previous pharmacokinetic studies have shown that Striant SR effectively produces physiological serum testosterone levels in hypogonadal men. Efficacy and safety data from previously unpublished studies over 2 years of continuous use indicate that Striant SR is effective long term in maintaining serum testosterone within a physiological range, is well tolerated and has a high level of patient acceptance. Striant® sustained-release (SR) is a mucoadhesive buccal tablet (30 mg testosterone, The Urology Company) that adheres to the gum surface in the mouth providing controlled- and sustained-release of testosterone over a 12-h dosing period, offering a unique and rational method of testosterone delivery. Striant SR is indicated for testosterone-replacement therapy (TRT) for male hypogonadism when testosterone deficiency has been confirmed by clinical features and biochemical tests. Pharmacokinetic studies have shown that testosterone is released from Striant SR in a manner similar to the normal daily rhythm of endogenous testosterone secretion, with serum levels rising rapidly after insertion and peak levels reached by the second 12-hourly dose with no accumulation over time. In clinical trials involving hypogonadal men receiving Striant SR for up to 2 years, mean serum testosterone levels have always remained within the normal range. Striant SR is well tolerated, with gum-related disorders (such as irritation, inflammation and gingivitis) and taste perversion being the most commonly reported adverse events, reported by 5.6-16.3% and 3.0-4.1% of patients, respectively. Once patients have become accustomed to it, Striant SR has a high level of patient acceptance. In a long-term study, 90% of patients rated the twice-daily dosing as acceptable, just under half preferred it to other forms of TRT that they have used and

  2. Testosterone treatment in elderly men.

    PubMed

    Srinivas-Shankar, U; Sharma, D

    2009-01-01

    Testosterone has been used in testicular and hypothalamo-pituitary diseases since the 1940s. There is growing interest in the use of testosterone in aging men, and this has stimulated research into the benefits of male hormone replacement. Testosterone treatment of men with hypogonadism might have beneficial effects on body composition, muscle strength, sexual function, and cognition. There are several modes of administration of the male hormone, with injectable testosterone esters and implanted testosterone pellets being the mainstay of treatment until recently. These preparations are increasingly being replaced by transdermal patches, gels, and long-acting parenteral preparations. Testosterone patches and gels are ideally for elderly men. Treatment with the male hormone is relatively safe, if patients are selected appropriately and monitored carefully. The most important adverse effects are on the prostate. In this review, we briefly discuss the indications, contraindications, and benefits of testosterone treatment. Further, we list the adverse effects, advantages, and disadvantages of various testosterone preparations in elderly men.

  3. Testosterone deficiency syndrome: benefits, risks, and realities associated with testosterone replacement therapy.

    PubMed

    Hassan, Jacob; Barkin, Jack

    2016-02-01

    Testosterone deficiency syndrome, which has sometimes been termed age-related or late-onset hypogonadism, is a syndrome characterized by both clinical manifestations as well as a biochemical deficiency of testosterone. This condition is associated with considerable morbidity and mortality, accounting for billions of dollars in health care costs. There is some evidence that suggests that restoring testosterone levels in these individuals may help to manage or delay progression of the associated morbidities. Furthermore, despite controversies in the literature and media, testosterone replacement has proven to be quite safe in most men with minimal if any adverse effects when dosing to achieve the eugonadal range. It is nevertheless very important for clinicians to be aware of the possible risks and contraindications of treatment to ensure proper patient selection and appropriate monitoring.

  4. Mouse Spermatogenesis Requires Classical and Nonclassical Testosterone Signaling.

    PubMed

    Toocheck, Corey; Clister, Terri; Shupe, John; Crum, Chelsea; Ravindranathan, Preethi; Lee, Tae-Kyung; Ahn, Jung-Mo; Raj, Ganesh V; Sukhwani, Meena; Orwig, Kyle E; Walker, William H

    2016-01-01

    Testosterone acts though the androgen receptor in Sertoli cells to support germ cell development (spermatogenesis) and male fertility, but the molecular and cellular mechanisms by which testosterone acts are not well understood. Previously, we found that in addition to acting through androgen receptor to directly regulate gene expression (classical testosterone signaling pathway), testosterone acts through a nonclassical pathway via the androgen receptor to rapidly activate kinases that are known to regulate spermatogenesis. In this study, we provide the first evidence that nonclassical testosterone signaling occurs in vivo as the MAP kinase cascade is rapidly activated in Sertoli cells within the testis by increasing testosterone levels in the rat. We find that either classical or nonclassical signaling regulates testosterone-mediated Rhox5 gene expression in Sertoli cells within testis explants. The selective activation of classical or nonclassical signaling pathways in Sertoli cells within testis explants also resulted in the differential activation of the Zbtb16 and c-Kit genes in adjacent spermatogonia germ cells. Delivery of an inhibitor of either pathway to Sertoli cells of mouse testes disrupted the blood-testis barrier that is essential for spermatogenesis. Furthermore, an inhibitor of nonclassical testosterone signaling blocked meiosis in pubertal mice and caused the loss of meiotic and postmeiotic germ cells in adult mouse testes. An inhibitor of the classical pathway caused the premature release of immature germ cells. Collectively, these observations indicate that classical and nonclassical testosterone signaling regulate overlapping and distinct functions that are required for the maintenance of spermatogenesis and male fertility.

  5. The association between perinatal testosterone concentration and early vocabulary development: a prospective cohort study.

    PubMed

    Hollier, Lauren P; Mattes, Eugen; Maybery, Murray T; Keelan, Jeffrey A; Hickey, Martha; Whitehouse, Andrew J O

    2013-02-01

    Prenatal exposure to testosterone is known to affect fetal brain maturation and later neurocognitive function. However, research on the effects of prenatal testosterone exposure has been limited by indirect measures of testosterone and small unrepresentative samples. This study investigated whether bioavailable testosterone (BioT) concentrations in umbilical cord blood are associated with expressive vocabulary development, in a large birth cohort. Cord blood samples were taken immediately after delivery and expressive vocabulary was measured at two years of age using the language development survey (LDS). BioT concentration significantly predicted vocabulary size in males (n=197), such that higher concentrations were associated with lower LDS scores, indicating smaller vocabulary. This relationship between BioT concentrations and vocabulary at aged 2 years was not observed in girls (n=176). Higher circulating prenatal testosterone concentrations at birth may be associated with reduced vocabulary in early childhood among boys.

  6. The relationships between body fatness, leptin, testosterone, and reproductive performance in ram lambs as affected by level and frequency of feeding.

    PubMed

    Swelum, Ayman Abdel-Aziz; Ayadi, Moez; Alhidary, Ibrahim; Alowaimer, Abdullah; Abouheif, Mohamed

    2017-02-01

    This study was carried out using 24 Najdi ram lambs of approximately 6.5 months old to evaluate the effects of feed restriction and frequency of feeding on hormone concentrations of leptin and testosterone, sexual behavior, and semen traits. Ram lambs were allotted equally into three feeding groups. The first group was used as a control and fed ad libitum. The second and third groups were restricted fed at 0.85 ad libitum and fed either once (R1M) or twice daily (R2M). Sexual behavior and semen evaluation were assessed during the sixth, seventh, and eighth weeks of the study. Blood samples were drawn at 1-hour pre-feeding on days 41, 48, and 55 of the study for the determination of serum leptin and testosterone concentrations. All lambs were slaughtered after 8 weeks of experimentation. Results showed that the restricted-fed groups had lower (P < 0.01) values for slaughter body weight, average daily gain, dry matter intake, internal fat, tail fat, body fat thickness, body wall thickness, and testes weight than the ad libitum group; these corresponding traits did not differ between both restricted-fed treatments. Leptin and testosterone concentrations in restricted-fed rams were (P < 0.01) lower and higher, respectively, than in the ad libitum rams; there were no differences between R1M and R2M groups. The restricted-fed rams had lower (P < 0.01) ejaculation latency time compared with control, whereas the percentage of sexually active rams and sexual desire score were not affected by feeding restriction or frequency of feeding. Sperm motility, progressive motility, and percentage of sperm moving at rapid speed were higher (P < 0.01) in feed-restricted rams than in the ad libitum rams. R1M rams had higher (P < 0.01) value for straightness and lower (P < 0.01) value for curvilinear velocity in comparison with the ad libitum group. Testosterone was correlated positively (P < 0.05) with sperm motility and progressive motility and negatively (P < 0

  7. Roles of Testosterone Replacement in Cardiac Ischemia-Reperfusion Injury.

    PubMed

    Pongkan, Wanpitak; Chattipakorn, Siriporn C; Chattipakorn, Nipon

    2016-01-01

    Testosterone is an anabolic steroid hormone, which is the major circulating androgen hormone in males. Testosterone levels decreasing below the normal physiological levels lead to a status known as androgen deficiency. Androgen deficiency has been shown to be a major risk factor in the development of several disorders, including obesity, metabolic syndrome, and ischemic heart disease. In the past decades, although several studies from animal models as well as clinical studies demonstrated that testosterone exerted cardioprotection, particularly during ischemia-reperfusion (I/R) injury, other preclinical and clinical studies have shown an inverse relationship between testosterone levels and cardioprotective effects. As a result, the effects of testosterone replacement on the heart remain controversial. In this review, reports regarding the roles of testosterone replacement in the heart following I/R injury are comprehensively summarized and discussed. At present, it may be concluded that chronic testosterone replacement at a physiological dose demonstrated cardioprotective effects, whereas acute testosterone replacement can cause adverse effects in the I/R heart.

  8. Extremely high levels of estradiol and testosterone in a case of polycystic ovarian syndrome. Hormone and clinical similarities with the phenotype of the alpha estrogen receptor null mice.

    PubMed

    Bartolone, L; Smedile, G; Arcoraci, V; Trimarchi, F; Benvenga, S

    2000-01-01

    A 19-year-old nulliparous hirsute woman was evaluated for the very high serum levels of testosterone (T) and estradiol (E2) measured in an outside laboratory. Menarche had occurred at 11 years and was followed by regular menses. We confirmed the high levels of T (9-16 ng/ml, nv 0.2-0.8) and E2 (>1,000 pg/ml, nv 30-120). LH and FSH were consistently high (73-118 mU/l and 18-29 mU/l, respectively; LH/FSH ratio=4.1-4.7) and responsive to iv GnRH (LH baseline=118 mU/I, 30 min=290; FSH baseline=25 mU/l, 30 min=46). The unstimulated values contrasted with those (LH=12, FSH=8 mU/I) measured in the outside laboratory, suggesting antigenically anomalous gonadotropins. 17-OH-progesterone was normal (0.5 ng/ml). After 1 mg dexamethasone, serum cortisol was normally suppressed (24-->0.4 microg/dl), T declined minimally (9-->8.6 ng/ml) and E2 remained high (>1,000 pg/ml). An exploratory laparotomy was performed, and two enlarged ovaries with multiple cysts as in a typical polycystic ovarian syndrome (PCOS) were seen. Before the wedge resection of the ovaries, hormones were assayed in the ovary veins (right ovary: T=30 ng/ml, Pg=17 ng/ml, E2=>5,000 pg/ml; left: T=14 ng/ml, Pg=14 ng/ml, E2=>5,000 pg/ml). Histologically, the follicle cysts showed luteinization of the theca interna; there was no evidence for ovary tumor in either ovary. After 21 days of 35 microg ethynyl-E2+2 mg cyproterone acetate (CA), E2=3,000 pg/ml, T=1.4 ng/ml, LH=10.5 mU/l and FSH=4.1 mU/I. After three cycles of the said therapy (but with 50 mg CA in the first 10 days of each cycle), E2 was 1,600 pg/ml, T 1.7 ng/ml, LH 7.1 and FSH 4.6 mU/I. Based on similarities with the phenotype of the alpha estrogen receptor knockout female mice (alphaERKO), one possible explanation for the puzzling clinical and biochemical picture of our patient is resistance of (alphaER to estrogens. This is the first case of PCOS with extremely high E2 and T. Thus, the differential diagnosis of high levels of E2 +/- T should include

  9. Testosterone and other anabolic steroids as cardiovascular drugs.

    PubMed

    Shapiro, J; Christiana, J; Frishman, W H

    1999-05-01

    There has been much interest in the effect of sex hormones on cardiovascular risk factors and as a therapeutic modality in both men and women. In this article, testosterone is considered as a possible therapy for cardiovascular disease. It has been shown that the level of serum testosterone decreases in men as they age. Healthy men with low testosterone levels have increased cardiovascular risk factors, including high fasting and 2-hour plasma glucose, serum triglycerides, total cholesterol and low-density lipoprotein (LDL) cholesterol, and apo A-I lipoprotein. Injections of testosterone to raise the levels to midnormal range have been shown to decrease total cholesterol and LDL cholesterol, while increasing high-density lipoprotein (HDL) cholesterol. Testosterone affects the clotting system by increasing thromboxane A (2) receptor activity and platelet aggregability. Testosterone has also been shown to augment the fibrinolytic system and antithrombin III activity. In men, testosterone has been shown to have antianginal effects, and endogenous levels have an inverse relationship to systolic blood pressure. Testosterone can be given in oral, injectable, pellet, and transdermal patch forms. There may be a role in administering testosterone to return men to normal physiologic range who have low serum levels. This treatment increases the risk of prostatic cancer, benign prostatism, erythrocytosis, and edema. No long-term studies of the effects of long-term testosterone replacement have been undertaken, so it is difficult to recommend this treatment as yet, but it is being considered as a therapy for augmenting skeletal muscle strength in patients with congestive heart failure.

  10. Testosterone and Child and Adolescent Adjustment: The Moderating Role of Parent-Child Relationships.

    ERIC Educational Resources Information Center

    Booth, Alan; Johnson, David R.; Granger, Douglas A.; Crouter, Ann C.; McHale, Susan

    2003-01-01

    In a sample of families with 6- to 18-year-olds, this study found that sons' and daughters' testosterone levels showed little direct connection to risk behavior or depressive symptoms. As parent-child relationship quality increased, testosterone-related adjustment problems were less evident. When relationship quality decreased, testosterone-linked…

  11. Has testosterone passed the test in premenopausal women with low libido? A systematic review

    PubMed Central

    Reed, Beverly G; Bou Nemer, Laurice; Carr, Bruce R

    2016-01-01

    Background There are limited evaluation and treatment options for low libido in premenopausal women. This review sought to evaluate the available evidence supporting the evaluation of testosterone serum levels and testosterone treatment of premenopausal women with low libido. Methods MEDLINE, PubMed, and ClinicalTrials.gov were searched for articles that referenced the evaluation of testosterone serum level and/or testosterone treatment on premenopausal women with low libido from 1995 to 2015. Additional references were obtained from the reference sections of other papers and from peer review. Studies that included only postmenopausal women were excluded. A total of 13 studies were reviewed in detail. Nine studies examined the relationship between testosterone serum levels and sexuality, an additional three studies examined the effect of testosterone treatment on premenopausal women with low libido, and one study examined both the topics. Results Six of the ten testosterone serum evaluation studies failed to show a significant association between testosterone serum level and libido. Only one out of four studies examining testosterone treatment in premenopausal women was able to show any clear improvement in libido; however, the effect was limited to only the intermediate dose of testosterone, with the low and high doses of testosterone not producing any effect. Conclusion The currently available evidence does not support testosterone serum evaluation or treatment in premenopausal women with low libido. Hence, further studies are warranted. PMID:27785108

  12. Understanding testosterone variation in a tropical lek-breeding bird.

    PubMed

    Ryder, Thomas B; Horton, Brent M; Moore, Ignacio T

    2011-08-23

    Male reproductive coalitions, in which males cooperate to attract females, are a rare strategy among vertebrates. While some studies have investigated ultimate aspects of these relationships, little is known about the mechanistic role that hormones play in modulating cooperative behaviours. Here, we examined male testosterone variation in a tropical lekking bird, the wire-tailed manakin (Pipra filicauda), which exhibits cooperative male-male display coalitions. We found that testosterone levels in territorial males were comparable to those of temperate breeding birds, a surprising result given their environmental, social and reproductive dynamics. In addition, social status rather than plumage was a strong predictor of testosterone variation. Territorial males had significantly higher testosterone levels than did two other plumage classes of floater males, who do not hold territories. We hypothesize that testosterone variation plays an important role in the establishment of male dominance hierarchies (competition), while concurrently facilitating stable display partnerships (cooperation).

  13. Off label therapies for testosterone replacement

    PubMed Central

    DiGiorgio, Lorenzo

    2016-01-01

    The incidence of hypogonadism has been steadily increasing over the last few years. Exogenous testosterone has been the standard treatment for hypogonadal men, but is associated with suppression of spermatogenesis as well as other possible adverse effects. There are other medications, currently considered “off label” for androgen replenishment, that exert their effect through modulation of the hypothalamic-gonadal axis. These medications increase endogenous testosterone levels and offer a different therapeutic approach. This review will focus on these alternative (off-label) therapies for androgen replacement in men. PMID:28078215

  14. Safety and efficacy of testosterone gel in the treatment of male hypogonadism

    PubMed Central

    Lakshman, Kishore M; Basaria, Shehzad

    2009-01-01

    Transdermal testosterone gels were first introduced in the US in 2000. Since then, they have emerged as a favorable mode of testosterone substitution. Serum testosterone levels reach a steady-state in the first 24 hours of application and remain in the normal range for the duration of the application. This pharmacokinetic profile is comparable to that of testosterone patch but superior to injectable testosterone esters that are associated with peaks and troughs with each dose. Testosterone gels are as efficacious as patches and injectable forms in their effects on sexual function and mood. Anticipated increases in prostate-specific antigen with testosterone therapy are not significantly different with testosterone gels, and the risk of polycythemia is lower than injectable modalities. Application site reactions, a major drawback of testosterone patches, occur less frequently with testosterone gels. However, inter-personal transfer is a concern if appropriate precautions are not taken. Superior tolerability and dose flexibility make testosterone gel highly desirable over other modalities of testosterone replacement. Androgel and Testim, the two currently available testosterone gel products in the US, have certain brand-specific properties that clinicians may consider prior to prescribing. PMID:19966909

  15. Testosterone Regulates Tight Junction Proteins and Influences Prostatic Autoimmune Responses

    PubMed Central

    Meng, Jing; Mostaghel, Elahe A.; Vakar-Lopez, Funda; Montgomery, Bruce; True, Larry; Nelson, Peter S.

    2015-01-01

    Testosterone and inflammation have been linked to the development of common age-associated diseases affecting the prostate gland including prostate cancer, prostatitis, and benign prostatic hypertrophy. We hypothesized that testosterone regulates components of prostate tight junctions which serve as a barrier to inflammation, thus providing a connection between age- and treatment-associated testosterone declines and prostatic pathology. We examined the expression and distribution of tight junction proteins in prostate biospecimens from mouse models and a clinical study of chemical castration, using transcript profiling, immunohistochemistry and electron microscopy. We determined that low serum testosterone is associated with reduced transcript and protein levels of Claudin 4 and Claudin 8, resulting in defective tight junction ultrastructure in benign prostate glands. Expression of Claudin 4 and Claudin 8 was negatively correlated with the mononuclear inflammatory infiltrate caused by testosterone deprivation. Testosterone suppression also induced an auto-immune humoral response directed toward prostatic proteins. Testosterone supplementation in castrate mice resulted in re-expression of tight junction components in prostate epithelium and significantly reduced prostate inflammatory cell numbers. These data demonstrate that tight junction architecture in the prostate is related to changes in serum testosterone levels, and identify an androgen-regulated mechanism that potentially contributes to the development of prostate inflammation and consequent pathology. PMID:21761342

  16. Testosterone Therapy Can Interact With Thrombophilia, Leading to Osteonecrosis.

    PubMed

    Glueck, Charles J; Riaz, Rashid; Prince, Marloe; Freiberg, Richard A; Wang, Ping

    2015-12-01

    Although this effect is not widely recognized, testosterone therapy can interact with thrombophilia, causing osteonecrosis. In 12 men and 4 women who had idiopathic osteonecrosis a median of 6 months after the onset of testosterone therapy, the authors examined the interaction between testosterone therapy and previously undiagnosed thrombophilia. The authors hypothesized that patients who had osteonecrosis after starting testosterone therapy were more likely than 110 normal control subjects or 48 patients who had osteonecrosis and were not receiving testosterone therapy to have thrombophilia. Measures of thrombophilia included Factor V Leiden, prothrombin, PAI-1 gene mutations, Factor VIII, Factor XI, anticardiolipin antibody immunoglobulin G or immunoglobulin M, and homocysteine values. In 10 cases, osteonecrosis occurred 6 months or less after the onset of testosterone therapy, and in all 16 cases, it occurred after a median of 6 months of testosterone therapy. Of the 16 cases, 5 (31%) were Factor V Leiden heterozygotes vs 2 of 109 (2%) healthy control subjects (P=.0003) and 4 of 48 patients who had osteonecrosis and were not receiving testosterone therapy (P=.04). Of the 16 cases, 4 (25%) had high (>150%) Factor VIII levels vs 7 of 103 (7%) healthy control subjects (P=.04), and 3 (19%) had high (>150%) Factor XI levels vs 3 of 101 (3%) healthy control subjects (P=.03). Of the 16 patients with osteonecrosis, 14 (88%) had at least 1 abnormal procoagulant value (of the 8 measured) vs 47 of 110 (43%) healthy control subjects (P=.0009). Of the 5 men whose serum estradiol level was measured while they were receiving testosterone therapy, this level was high (≥42.6 pg/mL) in 4. When testosterone therapy is given to patients with thrombophilia, they are at increased risk for osteonecrosis.

  17. Sex and testosterone effects on growth, immunity and melanin coloration of nestling Eurasian kestrels.

    PubMed

    Fargallo, Juan A; Martínez-Padilla, Jesús; Toledano-Díaz, Adolfo; Santiago-Moreno, Julián; Dávila, José A

    2007-01-01

    1. Sex differences in testosterone levels and sex-biased sensitivity to testosterone are the basis of some ideas postulated to account for sex-linked environmental vulnerability during early life. However, sex variation in circulating testosterone levels has been scarcely explored and never manipulated at post-natal stages of birds in the wild. 2. We measured and experimentally increased circulating testosterone levels in nestling Eurasian kestrels Falco tinnunculus. We investigated, possible sexual differences in testosterone levels and the effect of this hormone on growth (body mass and tarsus length) and cell-mediated immunity in males and females. We also explored testosterone effects on rump coloration, a highly variable melanin-based trait in male nestlings. We analysed data on circulating testosterone levels of nestlings in 15 additional bird species. 3. Increased levels of testosterone tended to negatively affect body condition, reduced cell-mediated immune responses in male and female nestlings and also diminished the expression of grey rump coloration in male nestlings. No sex differences were observed in testosterone levels in either control or increased testosterone group nestlings, and no interactions were found between sex and treatment. However, male nestlings showed a lower cell-mediated immune response than females in both groups. 4. Our results indicate first, that a high level of testosterone in all nestlings in a brood entails costs, at least in terms of immunity, coloration and probably growth. Secondly, sex differences in post-natal cell-mediated immunity, and consequently in the capacity to prevent diseases, cannot be explained by sex differences in circulating testosterone levels. Finally, by comparing published data at an interspecific level, contradictory sex patterns in circulating testosterone levels have been found, supporting the idea that circulating testosterone might not be a proximate factor causing sex-dependent vulnerability in

  18. Pubertal testosterone predicts mental rotation performance of young adult males.

    PubMed

    Vuoksimaa, Eero; Kaprio, Jaakko; Eriksson, C J Peter; Rose, Richard J

    2012-11-01

    Robust sex differences in some spatial abilities that favor males have raised the question of whether testosterone contributes to those differences. There is some evidence for prenatal organizational effects of testosterone on male-favoring spatial abilities, but not much is known about the role of pubertal testosterone levels on adult cognitive abilities. We studied the association between pubertal testosterone (at age 14) and cognitive performance in young adulthood (at age 21-23), assessing male-favoring, female-favoring, and sex-neutral cognitive domains in a population-based sample of 130 male and 178 female twins. Pubertal testosterone was negatively associated with performance in the Mental Rotation Test in young adult men (r=-.27), while among women no significant associations between testosterone and cognitive measures were detected. The significant association among men remained after controlling for pubertal development. Confirmatory within-family comparisons with one-sided significance testing yielded a negative correlation between twin pair differences in testosterone levels and Mental Rotation Test performances in 35 male twin pairs (r=-.32): the twin brother with higher testosterone performed less well on the Mental Rotation Test. That association was evident in 18 pairs of dizygotic male twin pairs (r=-.42; analysis controlling for shared environmental effects). In contrast, the association of differences was not evident among 17 monozygotic male twin pairs (r=-.07; analysis controlling for shared genetic influences). Results suggest that pubertal testosterone levels are related specifically to male-favoring spatial ability and only among men. Within-family analyses implicated possible shared genetic effects between pubertal testosterone and mental rotation ability.

  19. Testosterone, estradiol, ACTH and musical, spatial and verbal performance.

    PubMed

    Hassler, M; Gupta, D; Wollmann, H

    1992-01-01

    Testosterone, estradiol, and ACTH were determined in blood serum of 26 healthy males aged 19.16 and of 25 healthy females aged 18.77 years on average, and results were correlated with test scores of three spatial tests, a verbal fluency measure, and a test measuring general musical ability. In addition, hemispheric lateralization for verbal material and handedness was assessed. While testosterone and estradiol alone were not significantly related to any of the cognitive or musical tests, testosterone/estradiol ratio was significantly negatively correlated with spatial tests, and ACTH was significantly positively correlated with spatial and musical tests. Correlations were stronger in females than in males. The laterality index was significantly negatively correlated with testosterone in males indicating that right hemisphere involvement in verbal processing was associated with high testosterone levels.

  20. Does testosterone affect foraging behavior in male frogs?

    PubMed

    Desprat, Julia L; Mondy, Nathalie; Lengagne, Thierry

    2017-02-19

    During the breeding season, males often produce costly and extravagant displays or physical ornaments to attract females. Numerous studies have established that testosterone could directly influence the expression of certain sexual signals. However, few of these studies have focused on the indirect role that testosterone could play in modulating prey detection and visual performance to improve the foraging ability of males and hence their acquisition of nutritional resource. In the present study, we experimentally modified the testosterone levels of European tree frog males (Hyla arborea), staying in the natural range previously measured in the field, and we investigated the effect of testosterone on the foraging ability of individuals. Foraging capacities were measured on males placed in an arena with a virtual cricket moving on a computer screen. Our results demonstrated a significant effect of testosterone on the hunting behavior of H. arborea. We observed that testosterone reduced the orientation latency to virtual prey for supplemented males compared to controls. In addition, testosterone significantly increased the attack promptness of male frogs. Finally, our experiment did not demonstrate any impact of testosterone on male attack success.

  1. Testosterone, thrombophilia, thrombosis.

    PubMed

    Freedman, Joel; Glueck, Charles J; Prince, Marloe; Riaz, Rashid; Wang, Ping

    2015-05-01

    We screened previously undiagnosed thrombophilia (V Leiden-prothrombin mutations, Factors VIII and XI, homocysteine, and antiphospholipid antibody [APL] syndrome) in 15 men and 2 women with venous thromboembolism (VTE) or osteonecrosis 7 months (median) after starting testosterone therapy (TT), gel (30-50 mg/d), intramuscular (100-400 mg/wk), or human chorionic gonadotropin (HCG) (6000 IU/wk). Thrombophilia was studied in 2 healthy control groups without thrombosis (97 normal controls, 31 subjects on TT) and in a third control group (n = 22) with VTE, not on TT. Of the 17 cases, 76% had ≥1 thrombophilia vs 19% of 97 normal controls (P < 0.0001), vs 29% of 31 TT controls (P = 0.002). Cases differed from normal controls by Factor V Leiden (12% vs 0%, P = 0.021), by high Factor VIII (>150%) (24% vs 7%, P = 0.058), by high homocysteine (29% vs 5%, P = 0.007), and from both normal and TT controls for APL syndrome (18% vs 2%, P = 0.023, vs 0%, P = 0.04). Despite adequate anticoagulation with TT continued after the first deep venous thrombosis-pulmonary embolus (DVT-PE), 1 man sustained 3 DVT-PEs 5, 8, and 11 months later and a second man had 2 DVT-PEs 1 and 2 months later. Of the 10 cases with serum T measured on TT, 6 (60%) had supranormal T (>800 ng/dL) and of 9 with estradiol measured on TT, 7 (78%) had supranormal levels (>42.6 pg/mL). TT interacts with thrombophilia leading to thrombosis. TT continuation in thrombophilic men is contraindicated because of recurrent thrombi despite anticoagulation. Screening for thrombophilia before starting TT should identify subjects at high risk for VTE with an adverse the risk to benefit ratio for TT.

  2. Marriage and motherhood are associated with lower testosterone concentrations in women.

    PubMed

    Barrett, Emily S; Tran, Van; Thurston, Sally; Jasienska, Grazyna; Furberg, Anne-Sofie; Ellison, Peter T; Thune, Inger

    2013-01-01

    Testosterone has been hypothesized to modulate the trade-off between mating and parenting effort in males. Indeed, evidence from humans and other pair-bonded species suggests that fathers and men in committed relationships have lower testosterone levels than single men and men with no children. To date, only one published study has examined testosterone in relation to motherhood, finding that mothers of young children have lower testosterone than non-mothers. Here, we examine this question in 195 reproductive-age Norwegian women. Testosterone was measured in morning serum samples taken during the early follicular phase of the menstrual cycle, and marital and maternal status were assessed by questionnaire. Mothers of young children (age ≤3) had 14% lower testosterone than childless women and 19% lower testosterone than women who only had children over age 3. Among mothers, age of the youngest child strongly predicted testosterone levels. There was a trend towards lower testosterone among married women compared to unmarried women. All analyses controlled for body mass index (BMI), age, type of testosterone assay, and time of serum sample collection. This is the first study to look at testosterone concentrations in relation to marriage and motherhood in Western women, and it suggests that testosterone may differ with marital and maternal status in women, providing further corroboration of previous findings in both sexes.

  3. Melamine negatively affects testosterone synthesis in mice.

    PubMed

    Sun, Jiarui; Cao, Yinan; Zhang, Xinchen; Zhao, Qiling; Bao, Endong; Lv, Yingjun

    2016-12-01

    Several studies have found that melamine causes damage to the testes, epididymis and sperm. However, few studies have investigated the effect of melamine on the synthesis of testosterone, which plays an import role in testicular development and spermatogenesis. In present study, mice were orally administrated with 2, 10 or 50mg/kg of melamine for 28days. In these groups, various abnormalities were observed including disruption of the seminiferous tubule structure, an increased necrotic germ cells and sperm abnormalities, and a reduced sperm count. Melamine exposure also decreased the level of serum testosterone and levels of testicular StAR, P450scc and 17β-HSD. In addition, melamine exposure reduced the number of Leydig cells. Taken together, these results indicate that melamine exposure reduces the level of testosterone through down-regulation of StAR and testosterone synthetic enzyme expression and also a decreased number of Leydig cells. This may further affect testicular development and lead to sperm damage.

  4. Recent trends in the treatment of testosterone deficiency syndrome.

    PubMed

    Hong, Bum Sik; Ahn, Tai Young

    2007-11-01

    Testosterone deficiency syndrome (TDS) is defined as a clinical and biochemical syndrome associated with advancing age and is characterized by typical symptoms and deficiency in serum testosterone levels. TDS is a result of the interaction of hypothalamo-pituitary and testicular factors. Now, treatment of TDS with testosterone is still controversial due to a lack of large, controlled clinical trials on efficacy. The risks of treatment with testosterone appear to be minimal, although long-term studies on the safety of testosterone therapy are lacking. The aim of the therapy is to establish a physiological concentration of serum testosterone in order to correct the androgen deficiency, relieve its symptoms and prevent long-term sequelae. All of the available products, despite their varying pharmacodynamic and pharmacokinetic profiles, are able to reach this goal. Newer testosterone patches seem not to cause severe skin irritation. Testosterone gels minimize the skin irritation while providing flexibility in dosing and a low discontinuation rate. Oral testosterone undecanoate (TU) is free of liver toxicity. Recent formulation of oral TU markedly increased shelf-live, a major drawback in the older preparation. Producing swings in testosterone levels rising rapidly to the supraphysiological range is not the case with the new injectable long-acting preparation of TU. To be able to rapidly react and stop treatment in cases where side-effects and contraindications are detected, the short-acting transdermal and oral delivery modes have certain advantages. However, there is no evidence that the use of an injectable long-acting TU in men with TDS has limitations in clinical application for this reason. The use of dehydroepiandrosterone is still controversial because of a lack of well designed long-term trials, although some recent studies suggest positive effects on various body systems. Only a few studies have been carried out to investigate the effect of hCG (human

  5. Late-Onset Hypogonadism and Testosterone Replacement in Older Men.

    PubMed

    Bhattacharya, Rajib K; Bhattacharya, Shelley B

    2015-11-01

    Late-onset hypogonadism is an underdiagnosed and easily treated condition defined by low serum testosterone levels in men older than 65 years. When treated, a significant improvement in quality of life may be reached in this rapidly rising sector of the population. During the evaluation, laboratory tests and a full medication review should be performed to exclude other illnesses or adverse effects from medications. The major goal of treatment in this population is treating the symptoms related to hypogonadism. There has not been clear evidence supporting universally giving older men with low serum testosterone levels and hypogonadal symptoms testosterone replacement therapy.

  6. Testosterone and temperament traits in men: Longitudinal analysis.

    PubMed

    Määttänen, Ilmari; Jokela, Markus; Hintsa, Taina; Firtser, Sonja; Kähönen, Mika; Jula, Antti; Raitakari, Olli T; Keltikangas-Järvinen, Liisa

    2013-10-01

    Testosterone is the main male hormone that has been associated with various behavioral traits in humans and other animals. We investigated whether levels of total testosterone, free testosterone, and sex hormone binding globulin were associated with temperament traits in a population-based sample of Finnish men at two measurement times taken 6 years apart (n=686 in year 2001, n=727 in year 2007). Temperament was assessed using the Temperament and Character Inventory that consists of four temperament traits: novelty seeking, harm avoidance, reward dependence, and persistence. Higher levels of total and free testosterone were associated with higher novelty seeking (standardized B=0.103, p<0.001). This association was also observed in a longitudinal within-person analysis (B=0.084, p=0.008), suggesting that the association is not confounded by stable between-individual differences in other characteristics. Within-individual variation in total testosterone was associated with higher reward dependence, and higher levels of free testosterone were marginally associated with higher reward dependence. Reward dependence reflects the importance of social rewards to an individual. These results provide additional evidence for the stable and time-varying associations between testosterone and temperament in humans.

  7. Correlation Between Personality Traits and Testosterone Concentrations in Healthy Population

    PubMed Central

    Tajima-Pozo, Kazuhiro; Bayón, Camila; Díaz-Marsá, Marina; Carrasco, Jose Luis

    2015-01-01

    Objective: High plasma testosterone levels have been associated with aggression, sexual behaviour and social status. The aim of this paper was to study the correlation between basal plasma testosterone levels and personality variables in healthy participants. Materials and Methods: Fifty-four participants were randomly enrolled into this study. Basal plasma testosterone levels were measured between 8:30 am and 10 am. After 24 hours of blood drawing, each subject completed personality questionnaires. Results: Positive correlation between basal plasma testosterone levels and anti-social personality traits in both genders was observed (r = 0.336 and P < 0.018). Also, a positive correlation was observed between basal plasmatestosterone levels and criminal thinking traits (r = 0. 376, P < 0.05) and Millon compulsive (r = 0.386, P < 0.010) in both genders. In female participants, a positive correlation between basal plasmatestosterone levels and psychoticism (r = 0. 25, P < 0.019) and Cloninger AUTO TCI (r = 0.507, P < 0.004) was observed. In males participants positive correlation between baseline plasmatic Testosterone levels and Millon Antisocial trait (r = 0. 544, P < 0.19) and Millon Hypomania trait (r = 0. 485, P < 0.41) and Millon Drug Abuse trait (r = 0.632, P < 0.05) was reported. Conclusion: Our results suggest gender differences in clinical and personality variables related with basal plasma testosterone level. In men, high plasma testosterone levels were associated with clinical traits, substance abuse and hypomania. Women with higher basal testosterone levels showed higher scores on personality self-direction traits. PMID:26664080

  8. Testosterone Therapy and Prostate Cancer.

    PubMed

    Davidson, Emily; Morgentaler, Abraham

    2016-05-01

    Changes in understanding regarding the relationship of androgens and prostate cancer have led to changes in the use of testosterone therapy. The evidence supports a finite ability of androgens to stimulate prostate cancer growth, with a maximum achieved at low testosterone concentrations, called the saturation model. The saturation point corresponds with maximal androgenic stimulation at 250 ng/dL. Evidence is reviewed herein regarding the relationship of testosterone to prostate cancer and the relatively new practice of offering testosterone therapy to men with a history of prostate cancer. Although no prospective controlled trials have been performed, results have been reassuring.

  9. Testosterone Therapy May Have Benefits, but Risks Too

    MedlinePlus

    ... called "low T" (low testosterone levels), said Dr. Thomas Gill. He is a Yale University professor of ... but still not all questions are answered." SOURCES: Thomas Gill, M.D., professor, geriatrics, Yale University, New ...

  10. Evidence of sexual dimorphism in placental vitamin D metabolism: Testosterone inhibits calcitriol-dependent cathelicidin expression.

    PubMed

    Olmos-Ortiz, Andrea; García-Quiroz, Janice; López-Marure, Rebeca; González-Curiel, Irma; Rivas-Santiago, Bruno; Olivares, Aleida; Avila, Euclides; Barrera, David; Halhali, Ali; Caldiño, Felipe; Larrea, Fernando; Díaz, Lorenza

    2016-10-01

    Male fetus and neonates show increased immune vulnerability compared to females, which results in a higher risk of perinatal infections. These differences could partially be due to sex steroids differential modulation of vitamin D metabolism; since calcitriol, the most active vitamin D metabolite, regulates immune responses and transcriptionally induces the antimicrobial peptide cathelicidin in the human placenta. Calcitriol availability depends on CYP27B1 and CYP24A1 expression, the cytochromes involved in its synthesis and degradation, respectively. However, the effects of testosterone upon these enzymes and the final biological outcome upon the calcitriol-dependent immune-target cathelicidin in the placenta have not been studied. In this study we show that testosterone significantly inhibited CYP27B1 while stimulated CYP24A1 gene expression in cultured trophoblasts. These effects were accompanied by CREB activation through cAMP-independent and androgen receptor-dependent mechanisms. Male placental cotyledons showed reduced basal CYP27B1 and cathelicidin gene expression compared to females (P<0.05). Testosterone concentration was higher in the cord blood of male neonates (P=0.007), whereas cathelicidin levels were lesser compared to females (P=0.002). Altogether our results suggest that male placentas produce less cathelicidin due to decreased calcitriol bioavailability. We propose that the observed sex-dependent differences in placental vitamin D metabolism contribute in fetal responses to infections and could partially explain why the increased male fetuses immune vulnerability. Moreover, gestational hyperandrogenemia could adversely affect placental vitamin D metabolism independently of fetal sex.

  11. Pituitary and testis responsiveness of young male sheep exposed to testosterone excess during fetal development.

    PubMed

    Recabarren, Mónica P; Rojas-Garcia, Pedro P; Einspanier, Ralf; Padmanabhan, Vasantha; Sir-Petermann, Teresa; Recabarren, Sergio E

    2013-06-01

    Prenatal exposure to excess testosterone induces reproductive disturbances in both female and male sheep. In females, it alters the hypothalamus-pituitary-ovarian axis. In males, prenatal testosterone excess reduces sperm count and motility. Focusing on males, this study tested whether pituitary LH responsiveness to GNRH is increased in prenatal testosterone-exposed males and whether testicular function is compromised in the testosterone-exposed males. Control males (n=6) and males born to ewes exposed to twice weekly injections of 30  mg testosterone propionate from days 30 to 90 and of 40  mg testosterone propionate from days 90 to 120 of gestation (n=6) were studied at 20 and 30 weeks of age. Pituitary and testicular responsiveness was tested by administering a GNRH analog (leuprolide acetate). To complement the analyses, the mRNA expression of LH receptor (LHR) and that of steroidogenic enzymes were determined in testicular tissue. Basal LH and testosterone concentrations were higher in the testosterone-exposed-males. While LH response to the GNRH analog was higher in the testosterone-exposed males than in the control males, testosterone responses did not differ between the treatment groups. The testosterone:LH ratio was higher in the control males than in the testosterone-exposed males of 30 weeks of age, suggestive of reduced Leydig cell sensitivity to LH in the testosterone-exposed males. The expression of LHR mRNA was lower in the testosterone-exposed males, but the mRNA expression of steroidogenic enzymes did not differ between the groups. These findings indicate that prenatal testosterone excess has opposing effects at the pituitary and testicular levels, namely increased pituitary sensitivity to GNRH at the level of pituitary and decreased sensitivity of the testes to LH.

  12. Pharmacology of testosterone replacement therapy preparations

    PubMed Central

    Shoskes, Jennifer J.; Wilson, Meghan K.

    2016-01-01

    The goal of testosterone replacement therapy (TRT) is to return serum testosterone levels to within physiologic range and improve symptoms in hypogonadal men. Some of the symptoms aimed to improve upon include decreased libido, erectile dysfunction, infertility, hot flashes, depressed mood, and loss of muscle mass or hair. Clinical use of testosterone for replacement therapy began approximately 70 years ago. Over the decades, numerous preparations and formulations have been developed primarily focusing on different routes of delivery and thus pharmacokinetics (PKs). Currently the routes of delivery approved for use by the United States Food and Drug Administration encompasses buccal, nasal, subdermal, transdermal, and intramuscular (IM). Many factors must be considered when a clinician is choosing the most correct formulation for a patient. As this decision depends highly on the patient, active patient participation is important for effective selection. The aim of this review is to describe and compare all testosterone preparations currently available and approved by the United States Food and Drug Administration. Areas of focus will include pharmacology, PKs, adverse effects, and specifics related to individual delivery routes. PMID:28078214

  13. Validated HPLC method for determination of caffeine level in human plasma using synthetic plasma: application to bioavailability studies.

    PubMed

    Alvi, Syed N; Hammami, Muhammad M

    2011-04-01

    Several high-performance liquid chromatography (HPLC) methods have been described for the determination of caffeine in human plasma. However, none have been cross validated using synthetic plasma. The present study describes a simple and reliable HPLC method for the determination of the caffeine level in human plasma. Synthetic plasma was used to construct calibration curves and quality control samples to avoid interference by caffeine commonly present in donor's human plasma. After deproteination of plasma samples with perchloric acid, caffeine and antipyrine (internal standard, IS) were separated on a Waters Atlantis C18 column using a mobile phase of 15 mM potassium phosphate (pH 3.5) and acetonitrile (83:17, v/v), and monitored by photodiode array detector, with the wavelength set at 274 nm. The relationship between caffeine concentrations and peak area ratio (caffeine-IS) was linear over the range of 0.05-20 μg/mL. Inter-run coefficient of variation was ≤ 5.4% and ≤ 6.0% and bias was ≤ 3% and ≤ 7% using human and synthetic plasma, respectively. Mean extraction recovery from human plasma of caffeine and the IS was 91% and 86%, respectively. Caffeine in human plasma was stable for at least 24 h at room temperature or 12 weeks at -20 °C, and after three freeze-thaw cycles. The method was successfully applied to monitor caffeine levels in healthy volunteers with correction of caffeine levels using the mean ratio of the slopes of the calibration's curves constructed using human and synthetic plasma.

  14. Oxytocin, testosterone, and human social cognition.

    PubMed

    Crespi, Bernard J

    2016-05-01

    I describe an integrative social-evolutionary model for the adaptive significance of the human oxytocinergic system. The model is based on a role for this hormone in the generation and maintenance of social familiarity and affiliation across five homologous, functionally similar, and sequentially co-opted contexts: mothers with offspring, female and male mates, kin groups, individuals with reciprocity partners, and individuals within cooperating and competing social groups defined by culture. In each situation, oxytocin motivates, mediates and rewards the cognitive and behavioural processes that underlie the formation and dynamics of a more or less stable social group, and promotes a relationship between two or more individuals. Such relationships may be positive (eliciting neurological reward, reducing anxiety and thus indicating fitness-enhancing effects), or negative (increasing anxiety and distress, and thus motivating attempts to alleviate a problematic, fitness-reducing social situation). I also present evidence that testosterone exhibits opposite effects from oxytocin on diverse aspects of cognition and behaviour, most generally by favouring self-oriented, asocial and antisocial behaviours. I apply this model for effects of oxytocin and testosterone to understanding human psychological disorders centrally involving social behaviour. Reduced oxytocin and higher testosterone levels have been associated with under-developed social cognition, especially in autism. By contrast, some combination of oxytocin increased above normal levels, and lower testosterone, has been reported in a notable number of studies of schizophrenia, bipolar disorder and depression, and, in some cases, higher oxytocin involves maladaptively 'hyper-developed' social cognition in these conditions. This pattern of findings suggests that human social cognition and behaviour are structured, in part, by joint and opposing effects of oxytocin and testosterone, and that extremes of such joint

  15. Testosterone, cortisol, and human competition.

    PubMed

    Casto, Kathleen V; Edwards, David A

    2016-06-01

    Testosterone and cortisol figure prominently in the research literature having to do with human competition. In this review, we track the history of this literature, concentrating particularly on major theoretical and empirical contributions, and provide commentary on what we see as important unresolved issues. In men and women, athletic competition is typically associated with an increase in testosterone (T) and cortisol (C). Hormone changes in response to non-athletic competition are less predictable. Person (e.g., power motivation, mood, aggressiveness, social anxiety, sex, and baseline levels of T and C) and context (e.g., whether a competition is won or lost, the closeness of the competition, whether the outcome is perceived as being influenced by ability vs. chance, provocations) factors can influence hormone responses to competition. From early on, studies pointed to a positive relationship between T and dominance motivation/status striving. Recent research, however, suggests that this relationship only holds for individuals with low levels of C - this is the core idea of the dual-hormone hypothesis, and it is certain that the broadest applications of the hypothesis have not yet been realized. Individuals differ with respect to the extent to which they embrace competition, but the hormonal correlates of competitiveness remain largely unexplored. Although rapid increases in both T and C associated with competition are likely adaptive, we still know very little about the psychological benefits of these hormonal changes. Administration studies have and will continue to contribute to this inquiry. We close with a discussion of what, we think, are important methodological and mechanistic issues for future research.

  16. The Effect of Testosterone on Men With Andropause

    PubMed Central

    Sofimajidpour, Heshmatollah; Teimoori, Taher; Gharibi, Fardin

    2015-01-01

    Background: Andropause is the gradual reduction of the male sex hormone (testosterone) with increasing age. Its symptoms are sexual dysfunction, weakness, fatigue, insomnia, loss of motivation, mood disorders and reduction of bone density. Treatment of andropause with testosterone has been recently considered. Objectives: The aim of this study was to evaluate the effect of testosterone in the treatment of andropause in men. Patients and Methods: For men who met the inclusion criteria (50 years of age and older) laboratory tests and clinical examinations were conducted by an urologist in order to diagnose prostate cancer, prostate disease, urinary tract infection and active urinary retention. After obtaining consent, the patients were enrolled in the study. Data were analyzed using SPSS version 20. Descriptive statistics (frequency and percentage, mean, standard deviation) and the paired t-test were used to compare levels of testosterone. To determine the correlation between age and testosterone levels, the Pearson correlation was used. Finally, to compare the treatment processes during the treatment period the repeated measures ANOVA was used. Results: The mean age of patients was 56.57 ± 3.21 years. A total of 31 patients (39%) were smokers, among them 30% smoked daily, 2.5% weekly and 6% smoked for fun. The mean testosterone level before treatment was 240.6 ± 125.4 and at 1, 3 and 6 months after treatment the level was raised, so that at the end of the sixth months it was 578.7 ± 141.7. The level of increase was statistically significant (P = 0.0001). Conclusions: Treatment with testosterone in men over 50 years with andropause will increase testosterone levels and also quality of life, sexual desire, erection, energy levels, ability to exercise and feel the joy of life more than before. Depression was decreased and they had sleepy feelings after dinner. PMID:26756004

  17. Bill color, not badge size, indicates testosterone-related information in house sparrows

    PubMed Central

    Kempenaers, Bart; Dale, James

    2010-01-01

    The honesty of ornamental signals of quality is often argued to be enforced via costs associated with testosterone. It is still poorly understood, however, how seasonal variation of testosterone within individuals is related to the timing and extent of ornament development. Here, we studied inter- and intra-individual variability of plasma testosterone levels in a population of 150 captive male house sparrows (Passer domesticus) through the course of a full year. We further analyzed the relationship between plasma testosterone levels and two sexually dimorphic ornaments: badge size and bill coloration. Also, because of a known negative relation between molt and circulating testosterone levels, we analyzed the relationship between ornamentation and molt status during the fall. We found that testosterone levels increased towards the breeding season and decreased before the onset of annual molt. However, within individuals, relative testosterone titers demonstrated low repeatability between seasons. Plasma testosterone levels were not correlated with badge size in any season but were correlated strongly with bill coloration during all periods, except the breeding season when variation in bill color was low. Finally, we found that bill coloration strongly correlated with molt status during fall. Our results indicate that bill coloration, not badge size, is the best ornamental indicator of a “running average” of male testosterone in house sparrows and therefore the best potential indicator of qualities and/or behavioral strategies associated with testosterone. PMID:20730125

  18. Effect of estrogen and testosterone replacement therapy on cognitive fatigue.

    PubMed

    Möller, Marika Christina; Rådestad, Angelique Flöter; von Schoultz, Bo; Bartfai, Aniko

    2013-02-01

    Both estrogen and testosterone insufficiency has been associated with reduced psychological well-being including fatigue. However, hormonal replacement studies on fatigue are rare. Therefore, we wanted to study the effect of testosterone and estrogen replacement therapy on cognitive fatigue and the relation between sex hormone levels and cognitive fatigue in oophorectomized women. Fifty women with surgically induced menopause (mean age: 54.0 ± 2.9 years) were randomly assigned to treatment with estradiol valerate in combination with testosterone undecanoate or placebo for 24 weeks in a double-blind cross-over study. Neuropsychological tests and questionnaires were used to assess cognitive fatigue and psychological well-being. Cognitive fatigue was significantly associated to poor self-rated health and higher body mass index but not to general psychological well-being or sex hormone levels. Treatment with testosterone + estrogen had no significant effect on cognitive fatigue but the results indicated a curvilinear relation for hormonal levels. The estrogen/testosterone ratio was more related to functions rather than high or low hormone levels per se. We found that cognitive fatigue is frequent in oophorectomized women and negatively associated to self-perceived health and positively associated to BMI. A well-balanced ratio between estrogen and testosterone levels may be important for cognitive fatigue.

  19. Testosterone treatment in the aging male: myth or reality?

    PubMed

    Nigro, Nicole; Christ-Crain, Mirjam

    2012-03-19

    The definition of late onset hypogonadism in the aging male is controversially debated, and according to the latest literature consists of at least three especially sexual symptoms such as loss of morning erection, low sexual desire and erectile dysfunction as well as a total testosterone <8-11 nmol/l. Testosterone replacement therapy in the aging male has been shown to have a beneficial effect on muscle and fat mass as well as on bone mineral density, with more conflicting effects observed on muscle strength, sexual function, mood and quality of life. The prescriptions for testosterone products for the aging male increased by over 170% in the previous five years. Furthermore, there is a lot of epidemiological data showing an inverse relationship between testosterone levels and obesity, insulin resistance, the metabolic syndrome and type 2 diabetes mellitus. However, only few small randomised placebo-controlled studies have investigated the effect of testosterone replacement therapy on insulin resistance and HbA1c levels, with controversial results. Importantly, so far the long-term safety and efficacy of testosterone replacement therapy has not been established. Although until now no clear evidence has been found that testosterone replacement therapy has a causative role in prostate cancer or indeed in changes of the biology of the prostate, in a recent meta-analysis a 4-fold increased risk of prostate-associated event rates in testosterone treated elderly men sounds a note of caution. Also the risk for cardiovascular events is still not clear and caution is warranted especially in elderly men with cardiovascular disease and limited mobility. In summary, the actual available evidence of long-term risks and outcome of testosterone replacement therapy is still very limited and carefully designed placebo-controlled trials of testosterone administration to assess the risks and benefits of such a therapy are required. Until then, testosterone treatment in elderly men

  20. The role of testosterone therapy in cardiovascular mortality: culprit or innocent bystander?

    PubMed

    Tanna, Monique S; Schwartzbard, Arthur; Berger, Jeffery S; Alukal, Joseph; Weintraub, Howard

    2015-03-01

    Testosterone therapy is recommended for men with symptomatic androgen deficiency and unequivocally low testosterone levels. Although the prevalence of hypogonadism seems relatively constant, studies of prescribing patterns in both the United States and the United Kingdom show a dramatic increase in testosterone prescription in recent years, possibly due to increased marketing and inappropriate therapy. Concurrent with this, there has been growing concern regarding the potential adverse effects of testosterone therapy, particularly its cardiovascular risks. In this review, we present our current understanding of the implications of testosterone deficiency, as well as the conflicting evidence surrounding the cardiovascular effects of testosterone replacement therapy. Although there is a lack of adequate data, based on the current evidence, we conclude that testosterone therapy can be safely considered in men with appropriately diagnosed clinical androgen deficiency and increased cardiovascular risk after a thorough discussion of potential risks and with guideline recommended safety monitoring.

  1. Testosterone levels and their associations with lifetime number of opposite sex partners and remarriage in a large sample of American elderly men and women.

    PubMed

    Pollet, Thomas V; van der Meij, Leander; Cobey, Kelly D; Buunk, Abraham P

    2011-06-01

    Testosterone (T) has been argued to modulate mating and parenting behavior in many species, including humans. The role of T for these behaviors has been framed as the challenge hypothesis. Following this hypothesis, T should be positively associated with the number of opposite sex partners a male has. Indeed research in humans has shown that T is positively related to the number of opposite sex partners a young man has had. Here we test, in both men and women, whether this relationship extends to the lifetime number of sex partners. We also explored whether or not T was associated with current marital status, partnership status and whether or not the participant remarried. Using a large sample of elderly men and women (each sample n>700), we show that T is positively and sizably associated with the number of opposite sex partners in men. When controlling for potential confounding variables such as educational attainment, age, BMI, ethnicity, specific use of a medication and time of sampling this effect remained. For women, the relationship between T and number of opposite sex partners was positive but did not prove to be robust. In both men and women there was no evidence for an association between T and current marital status and partnership status (being in a relationship or not). However, remarriage was positively associated with T, but only in males. Results are discussed with reference to the literature on T and sex partners, remarriage and more broadly the challenge hypothesis.

  2. Bioavailability of cyanide after consumption of a single meal of foods containing high levels of cyanogenic glycosides: a crossover study in humans.

    PubMed

    Abraham, Klaus; Buhrke, Thorsten; Lampen, Alfonso

    2016-03-01

    The acute toxicity of cyanide is determined by its peak levels reached in the body. Compared to the ingestion of free cyanide, lower peak levels may be expected after consumption of foods containing cyanogenic glycosides with the same equivalent dose of cyanide. This is due to possible delayed and/or incomplete release of cyanide from the cyanogenic glycosides depending on many factors. Data on bioavailability of cyanide after consumption of foods containing high levels of cyanogenic glycosides as presented herein were necessary to allow a meaningful risk assessment for these foods. A crossover study was carried out in 12 healthy adults who consumed persipan paste (equivalent total cyanide: 68 mg/kg), linseed (220 mg/kg), bitter apricot kernels (about 3250 mg/kg), and fresh cassava roots (76-150 mg/kg), with each "meal" containing equivalents of 6.8 mg cyanide. Cyanide levels were determined in whole blood using a GC-MS method with K(13)C(15)N as internal standard. Mean levels of cyanide at the different time points were highest after consumption of cassava (15.4 µM, after 37.5 min) and bitter apricot kernels (14.3 µM, after 20 min), followed by linseed (5.7 µM, after 40 min) and 100 g persipan (1.3 µM, after 105 min). The double dose of 13.6 mg cyanide eaten with 200 g persipan paste resulted in a mean peak level of 2.9 µM (after 150 min). An acute reference dose of 0.075 mg/kg body weight was derived being valid for a single application/meal of cyanides or hydrocyanic acid as well as of unprocessed foods with cyanogenic glycosides also containing the accompanying intact β-glucosidase. For some of these foods, this approach may be overly conservative due to delayed release of cyanide, as demonstrated for linseed. In case of missing or inactivated β-glucosidase, the hazard potential is much lower.

  3. [The importance of testosterone in the treatment of metabolic syndrome in men].

    PubMed

    Kempisty-Zdebik, Ewa; Zdebik, Aleksander

    2012-01-01

    Testosterone deficiency syndrome is being seen in increasing percentage of men with middle and old age. Besides the typical deterioration of sexual function there is predisposition to metabolic syndrome and increased risk of cardiovascular diseases. The similarity of the effects of testosterone substitution and the dietary treatment led the authors to a retrospective analysis of patient data treated for testosterone deficiency syndrome. Data on 341 patients aged over 45 years with metabolic syndrome and diabetes, meeting criteria for the diagnosis of testosterone deficiency syndrome were divided into 5 groups: T--testosterone substitution without additional diet, T-Low-Carb--testosterone and low carbohydrate diet, T-Fat-Low--testosterone and low fat diet, Carb-Low--only low carbohydrate diet, Fat-Low--only low fat diet. We analyzed change in body weight, waist circumference, blood pressure, fasting glucose, HbAlc, HDL cholesterol and triglyceride levels within 6 months from the start of observation. The best results of all investigated parameters were obtained in patients treated with testosterone and low-carbohydrate diet and in the group treated with testosterone and low-fat diet. Slightly worse results in the group received the same diets and the worst in the group treated only with testosterone. The improvement obtained in the total testosterone therapy and diet was much greater than the simple sum of the effects of both methods witch suggests the existence of synergies.

  4. Patterns of testosterone in three Nearctic-Neotropical migratory songbirds during spring passage.

    PubMed

    Covino, Kristen M; Morris, Sara R; Moore, Frank R

    2015-12-01

    Preparation for breeding may overlap extensively with vernal migration in long-distance migratory songbirds. Testosterone plays a central role in mediating this transition into breeding condition by facilitating changes to physiology and behavior. While changes in testosterone levels are well studied in captive migrants, these changes are less well known in free-living birds. We examined testosterone levels in free-living Nearctic-Neotropical migrants of three species during their vernal migration. Testosterone levels increased during the migratory period in males of all three species but significantly so in only two. Testosterone levels in females remained the same throughout their migration. Our results support the extensive overlap between vernal migration and breeding preparation in male songbirds. The pattern of testosterone changes during vernal migration is far from clear in females.

  5. Flavonoid Bioavailability and Attempts for Bioavailability Enhancement

    PubMed Central

    Thilakarathna, Surangi H.; Rupasinghe, H. P. Vasantha

    2013-01-01

    Flavonoids are a group of phytochemicals that have shown numerous health effects and have therefore been studied extensively. Of the six common food flavonoid classes, flavonols are distributed ubiquitously among different plant foods whereas appreciable amounts of isoflavones are found in leguminous plant-based foods. Flavonoids have shown promising health promoting effects in human cell culture, experimental animal and human clinical studies. They have shown antioxidant, hypocholesterolemic, anti-inflammatory effects as well as ability to modulate cell signaling and gene expression related disease development. Low bioavailability of flavonoids has been a concern as it can limit or even hinder their health effects. Therefore, attempts to improve their bioavailability in order to improve the efficacy of flavonoids are being studied. Further investigations on bioavailability are warranted as it is a determining factor for flavonoid biological activity. PMID:23989753

  6. Testosterone replacement attenuates cognitive decline in testosterone-deprived lean rats, but not in obese rats, by mitigating brain oxidative stress.

    PubMed

    Pintana, Hiranya; Pongkan, Wanpitak; Pratchayasakul, Wasana; Chattipakorn, Nipon; Chattipakorn, Siriporn C

    2015-10-01

    Testosterone replacement improves metabolic parameters and cognitive function in hypogonadism. However, the effects of testosterone therapy on cognition in obese condition with testosterone deprivation have not been investigated. We hypothesized that testosterone replacement improves cognitive function in testosterone-deprived obese rats by restoring brain insulin sensitivity, brain mitochondrial function, and hippocampal synaptic plasticity. Thirty male Wistar rats had either a bilateral orchiectomy (ORX: O, n = 24) or a sham operation (S, n = 6). ORX rats were further divided into two groups fed with either a normal diet (NDO) or a high-fat diet (HFO) for 12 weeks. Then, ORX rats in each dietary group were divided into two subgroups (n = 6/subgroup) and were given either castor oil or testosterone (2 mg/kg/day, s.c.) for 4 weeks. At the end of this protocol, cognitive function, metabolic parameters, brain insulin sensitivity, hippocampal synaptic plasticity, and brain mitochondrial function were determined. We found that testosterone replacement increased peripheral insulin sensitivity, decreased circulation and brain oxidative stress levels, and attenuated brain mitochondrial ROS production in HFO rats. However, testosterone failed to restore hippocampal synaptic plasticity and cognitive function in HFO rats. In contrast, in NDO rats, testosterone decreased circulation and brain oxidative stress levels, attenuated brain mitochondrial ROS production, and restored hippocampal synaptic plasticity as well as cognitive function. These findings suggest that testosterone replacement improved peripheral insulin sensitivity and decreased oxidative stress levels, but failed to restore hippocampal synaptic plasticity and cognitive function in testosterone-deprived obese rats. However, it provided beneficial effects in reversing cognitive impairment in testosterone-deprived non-obese rats.

  7. Estimating relative bioavailability of soil lead in the mouse.

    PubMed

    Bradham, Karen D; Green, William; Hayes, Hunter; Nelson, Clay; Alava, Pradeep; Misenheimer, John; Diamond, Gary L; Thayer, William C; Thomas, David J

    2016-01-01

    Lead (Pb) in soil is an important exposure source for children. Thus, determining bioavailability of Pb in soil is critical in evaluating risk and selecting appropriate strategies to minimize exposure. A mouse model was developed to estimate relative bioavailability of Pb in NIST SRM 2710a (Montana 1 Soil). Based on Pb levels in tissues, the mean relative bioavailability of this metal in this soil was 0.5. Estimates of relative bioavailabilities derived from mouse compared favorably with those obtained in juvenile swine. The mouse model is thus an efficient and inexpensive method to obtain estimates of relative bioavailability of soil Pb.

  8. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  9. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  10. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  11. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  12. 21 CFR 556.710 - Testosterone propionate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Testosterone propionate. 556.710 Section 556.710... Tolerances for Residues of New Animal Drugs § 556.710 Testosterone propionate. No residues of testosterone, resulting from the use of testosterone propionate, are permitted in excess of the following increments...

  13. Testosterone restoration using enclomiphene citrate in men with secondary hypogonadism: a pharmacodynamic and pharmacokinetic study

    PubMed Central

    Wiehle, Ronald; Cunningham, Glenn R; Pitteloud, Nelly; Wike, Jenny; Hsu, Kuang; Fontenot, Gregory K; Rosner, Michele; Dwyer, Andrew; Podolski, Joseph

    2013-01-01

    Objectives To determine the pharmacodynamic profile of serum total testosterone and luteinizing hormone (LH) levels in men with secondary hypogonadism after initial and chronic daily oral doses of enclomiphene citrate vs transdermal testosterone. To determine the effects of daily oral doses of enclomiphene citrate in comparison with transdermal testosterone on other hormones and markers in men with secondary hypogonadism. Patients and Methods This was a randomized, single-blind, two-centre, phase II study to evaluate the effects of three different doses of enclomiphene citrate (6.25, 12.5 and 25 mg) vs transdermal testosterone on 24-h LH and total testosterone in otherwise normal healthy men with secondary hypogonadism. Forty-eight men were enrolled in the trial (the intent-to-treat population), but four men had testosterone levels >350 ng/dL at baseline. Forty-four men completed the study per protocol. All subjects enrolled in this trial had serum total testosterone in the low range (<350 ng/dL) and had low to normal LH (<12 IU/L) on at least two occasions. Total testosterone and LH levels were assessed each hour for 24 h to examine the effects at each of three treatment doses of enclomiphene citrate vs a standard dose (5 g) of transdermal testosterone. In the initial profile, total testosterone and LH were determined in a naïve population after a single initial oral or transdermal treatment (day 1). This was contrasted to that seen after 6 weeks of continuous daily oral or transdermal treatment (day 42). The pharmacokinetics of enclomiphene citrate were assessed in a select subpopulation. Serum samples were obtained over the course of the study to determine the levels of various hormones and lipids. Results After 6 weeks of continuous use, the mean (sd) concentration of total testosterone at day 42 was 604 (160) ng/dL for men taking the highest dose of enclomiphene citrate (enclomiphene citrate, 25 mg daily) and 500 (278) ng in those men treated with transdermal

  14. Increased testosterone to cortisol ratio in psychopathy

    PubMed Central

    Glenn, Andrea L.; Raine, Adrian; Schug, Robert A.; Gao, Yu; Granger, Douglas A.

    2011-01-01

    Only a few studies have examined hormones in psychopathy and results have been mixed. It has been suggested that since hormone systems are highly interconnected, it may be important to examine multiple systems simultaneously to gain a clearer picture of how hormones work together to predispose for a certain construct. In the present study, we attempt to clarify the role of the hormones cortisol and testosterone in psychopathy by examining both hormones in a community sample of 178 adults demonstrating a wide range of psychopathy scores. Results showed that psychopathy scores were associated with an increased ratio of testosterone (baseline) to cortisol responsivity to a stressor. Psychopathy was not associated with either of these measures independently, or with baseline cortisol levels. These findings suggest that these highly interconnected hormone systems may work in concert to predispose to psychopathy. PMID:21133509

  15. Could you have low testosterone?

    MedlinePlus

    ... menopause; Andropause; Testosterone deficiency; Androgen deficiency of the aging male; Late-onset hypogonadism ... Some symptoms may be a normal part of aging. For example, it is normal to feel less ...

  16. The biocide tributyltin reduces the accumulation of testosterone as fatty acid esters in the mud snail (Ilyanassa obsoleta).

    PubMed Central

    Gooding, Meredith P; Wilson, Vickie S; Folmar, Leroy C; Marcovich, Dragoslav T; LeBlanc, Gerald A

    2003-01-01

    Imposex, the development of male sex characteristics by female gonochoristic snails, has been documented globally and is causally associated with exposure to the ubiquitous environmental contaminant tributyltin (TBT). Elevated testosterone levels in snails also are associated with TBT, and direct exposure to testosterone has been shown to cause imposex. We discovered previously that the mud snail (Ilyanassa obsoleta)biotransforms and retains excess testosterone primarily as fatty acid esters. The purpose of this study was to determine whether TBT interferes with the esterification of testosterone, resulting in the elevated free (unesterified) testosterone levels associated with imposex. Exposure of snails to environmentally relevant concentrations of TBT (> or = 1.0 ng/L as tin) significantly increased the incidence of imposex. Total (free + esterified) testosterone levels in snails were not altered by TBT; however, free testosterone levels increased with increasing exposure concentration of TBT. TBT-exposed snails were given [14C

  17. Transmucosal delivery of testosterone in rabbits using novel bi-layer mucoadhesive wax-film composite disks.

    PubMed

    Jay, Steven; Fountain, William; Cui, Zhengrong; Mumper, Russell J

    2002-09-01

    Testosterone exhibits very low oral bioavailability because of its low aqueous solubility and extensive first-pass metabolism. The purpose of this study was to develop a novel bi-layer mucoadhesive wax-film composite (WFC), and to test the relative bioavailability of testosterone via the buccal route in rabbits. The release rate of testosterone from optimal WFCs (3/8-in. diameter) per unit surface area was 5.6 microg x cm(2) x mL(-1) x min(-1) and was zero-order. Bi-layer WFCs (average weight of 14 +/- 2.6 mg and thickness of 186 +/- 34 microns) containing 4 mg of testosterone were applied to the buccal pouch of anesthetized New Zealand white rabbits. Rabbits (n = 3) injected intravenously had C(max) and area under the curve values of 1200 +/- 46 ng/mL, and 48,227 +/- 12,995 ng x min/mL, respectively. Rabbits (n = 3) dosed via the buccal pouch had C(max), T(max), and area under the curve values of 127 +/- 13 ng/mL, 200 +/- 35 min, and 24,221 +/- 1543 ng x min/mL. The relative bioavailability for rabbits treated with the WFC was 50.2 +/- 3.2% with a coefficient of variation of 6.4%. It was concluded that these bi-layer mucoadhesive WFCs disks could deliver physiologically relevant amounts of insoluble drugs such as testosterone across the buccal mucosa.

  18. Growing Up Or Growing Old? Cellular Aging Linked With Testosterone Reactivity To Stress In Youth

    PubMed Central

    Drury, Stacy S.; Shirtcliff, Elizabeth A.; Shachet, Andrew; Phan, Jenny; Mabile, Emily; Brett, Zoë H.; Wren, Michael; Esteves, Kyle; Theall, Katherine P.

    2014-01-01

    Background Given the established relation between testosterone and aging in older adults, we tested whether buccal telomere length (TL), an established cellular biomarker of aging, was associated with testosterone levels in youth. Methods Children, mean age 10.2 years, were recruited from the greater New Orleans area and salivary testosterone was measured during both an acute stressor and diurnally. Buccal TL was measured using monochrome multiplex quantitative real-time PCR (MMQ-PCR). Testosterone and telomere length data was available on 77 individuals. The association between buccal TL and testosterone was tested using multivariate Generalized Estimating Equations (GEE) to account for clustering of children within families. Results Greater peak testosterone levels (β=-0.87, p < 0.01) and slower recovery (β=-0.56, p < 0.01) and reactivity (β = -1.22, p < 0.01) following a social stressor were significantly associated with shorter buccal TL after controlling for parental age at conception, child age, sex, sociodemographic factors and puberty. No association was initially present between diurnal measurements of testosterone or morning basal testosterone levels and buccal TL. Sex significantly moderated the relation between testosterone reactivity and buccal TL. Conclusions The association between testosterone and buccal TL supports gonadal maturation as a developmentally sensitive biomarker of aging within youth. As stress levels of testosterone were significantly associated with buccal TL, these findings are consistent with the growing literature linking stress exposure and accelerated maturation. The lack of association of diurnal testosterone or morning basal levels with buccal TL bolsters the notion of a shared stress-related maturational mechanism between cellular stress and the hypothalamic pituitary gonadal (HPG) axis. These data provide novel evidence supporting the interaction of aging, physiologic stress and cellular processes as an underlying

  19. 3,3 diindolylmethane leads to apoptosis, decreases sperm quality, affects blood estradiol 17 β and testosterone, oestrogen (α and β) and androgen receptor levels in the reproductive system in male rats.

    PubMed

    Aksu, E H; Akman, O; Ömür, A D; Karakuş, E; Can, I; Kandemir, F M; Dorman, E; Uçar, Ö

    2016-12-01

    3,3 Diindolylmethane (DIM) is a major digestive product of indole-3 carbinol, obtained from Brassica family vegetables such as broccoli, cabbage and Brussels sprouts. This study aimed to investigate the effects of DIM on sperm parameters, histological structures of testicular tissues, blood testosterone (T) and estradiol 17-β (E2) in male rats. Thirty-eight male Sprague Dawley rats were used. Rats were divided into four groups: Group I: referred as Control group, received corn oil only; Group II: as DIM-10, rats received 10 mg kg(-1) DIM; Group III: as DIM-50, rats received 50 mg kg(-1) DIM; Group IV: as DIM-100, received 100 mg kg(-1) DIM during 53 days. Spermatological parameters, malondialdehyde (MDA) levels of testes and serum T and E2 levels were assayed. Histopathological examinations of tests were done. DIM caused an increase in MDA levels. It decreased motility and live sperm rates and increased degeneration of testicular tissues. While DIM-10 did not affect abnormal sperm rate, higher concentrations increased the abnormalities. Sperm density was higher in DIM-10 groups when compared to both other groups. Only DIM-50 had an anti-androgenic effect among all groups. Only, DIM-10 showed anti-estrogenic activity as compared to higher DIM groups. In conclusion, DIM (i) had side effect on some sperm characteristics, (ii) increased the MDA levels and (iii) led to histological degeneration of testicular tissues and apoptosis in a dose-dependent manner.

  20. Testosterone, cortisol and anxiety in elite field hockey players.

    PubMed

    Aguilar, Raúl; Jiménez, Manuel; Alvero-Cruz, José R

    2013-07-02

    The aim of the present study was to assess the change in the levels of testosterone and cortisol after victory and defeat in male field hockey players during an important tournament. In the beginning of the game series, the players were ranked very closely to achieve (for the first time) the championship rising to The Honor Division-A, the highest status national category. The first game resulted in a 7-4 victory, the second game resulted in a 6-1 victory, and the third game resulted in a 1-2 defeat. As expected, there were changes in testosterone levels after the competition, dropping in the game which ended in defeat, and rising slightly in the two games which ended in victory; there were also changes in cortisol levels, rising in the game which ended in defeat, and showing no variations in the games which ended in victory; correlational analyses congruently showed that defeat led to rises in cortisol whereas victory led to rises in testosterone; anticipatory somatic anxiety was related to cortisol levels prior to games, and physical exertion during competition was related to the change in testosterone levels (suggesting an inhibitory effect) but not to the change in cortisol levels. Hence, this pattern of hormonal responses to a real-life dominance challenge complied with Mazur's (1985) [16] biosocial model of status and dominance motivation, by showing that testosterone and cortisol are linked to victory and defeat in a theoretically predictable fashion.

  1. Mechanism of testosterone deficiency in the transgenic sickle cell mouse.

    PubMed

    Musicki, Biljana; Zhang, Yuxi; Chen, Haolin; Brown, Terry R; Zirkin, Barry R; Burnett, Arthur L

    2015-01-01

    Testosterone deficiency is associated with sickle cell disease (SCD), but its underlying mechanism is not known. We investigated the possible occurrence and mechanism of testosterone deficiency in a mouse model of human SCD. Transgenic sickle male mice (Sickle) exhibited decreased serum and intratesticular testosterone and increased luteinizing hormone (LH) levels compared with wild type (WT) mice, indicating primary hypogonadism in Sickle mice. LH-, dbcAMP-, and pregnenolone- (but not 22-hydroxycholesterol)- stimulated testosterone production by Leydig cells isolated from the Sickle mouse testis was decreased compared to that of WT mice, implying defective Leydig cell steroidogenesis. There also was reduced protein expression of steroidogenic acute regulatory protein (STAR), but not cholesterol side-chain cleavage enzyme (P450scc), in the Sickle mouse testis. These data suggest that the capacity of P450scc to support testosterone production may be limited by the supply of cholesterol to the mitochondria in Sickle mice. The sickle mouse testis exhibited upregulated NADPH oxidase subunit gp91phox and increased oxidative stress, measured as 4-hydroxy-2-nonenal, and unchanged protein expression of an antioxidant glutathione peroxidase-1. Mice heterozygous for the human sickle globin (Hemi) exhibited intermediate hypogonadal changes between those of WT and Sickle mice. These results demonstrate that testosterone deficiency occurs in Sickle mice, mimicking the human condition. The defects in the Leydig cell steroidogenic pathway in Sickle mice, mainly due to reduced availability of cholesterol for testosterone production, may be related to NADPH oxidase-derived oxidative stress. Our findings suggest that targeting testicular oxidative stress or steroidogenesis mechanisms in SCD offers a potential treatment for improving phenotypic changes associated with testosterone deficiency in this disease.

  2. Testosterone production and spermatogenic damage induced by organophosphorate pesticides.

    PubMed

    Contreras, H R; Paredes, V; Urquieta, B; Del Valle, L; Bustos-Obregón, E

    2006-12-01

    Parathion is an organophosphorate pesticide amply used in agriculture. Many alterations induced by organophosphorate pesticides have been described, such as: cytogenetic alterations in germinal cells, oligozoospermia and teratozoospermia in the mouse. The effect of Parathion, both pure (PP) and commercial (PC), on mouse interstitial cell testosterone production was evaluated in vivo and in vitro. Male mice were intraperitoneally injected with a single dose of 1/3 LD50 of Parathion, both PP and PC. The animals were sacrificed at 1, 8 and 40 days post injection to evaluate the impact of disrupting testosterone production on spermatogonia, spermatocytes and elongated spermatids. The plasma testosterone was assayed by standard radioimmunoanalysis. The same method was used to assay testosterone in the culture medium of interstitial cells obtained from the control and Parathion treated animals at the same time intervals. Sperm count, sperm teratozoospermia and tubular blockage were analyzed for an appraisal of spermatogenesis. Increase in the teratozoospermia and tubular blockage was detected in the PP and PC group at 8 and 40 days post injection. Plasma testosterone levels drop significantly at 8 days and recovered slowly at 40 days only in PP animals as detected in vivo, implying interference of testicular steroidogenesis due to the toxicant. Recuperation of normality occurs at long time intervals. In conclusion, Parathion disturbs the synthesis of testosterone in mice affecting qualitatively the spermatogenesis

  3. The benefits and risks of testosterone replacement therapy: a review

    PubMed Central

    Bassil, Nazem; Alkaade, Saad; Morley, John E

    2009-01-01

    Increased longevity and population aging will increase the number of men with late onset hypogonadism. It is a common condition, but often underdiagnosed and undertreated. The indication of testosterone-replacement therapy (TRT) treatment requires the presence of low testosterone level, and symptoms and signs of hypogonadism. Although controversy remains regarding indications for testosterone supplementation in aging men due to lack of large-scale, long-term studies assessing the benefits and risks of testosterone-replacement therapy in men, reports indicate that TRT may produce a wide range of benefits for men with hypogonadism that include improvement in libido and sexual function, bone density, muscle mass, body composition, mood, erythropoiesis, cognition, quality of life and cardiovascular disease. Perhaps the most controversial area is the issue of risk, especially possible stimulation of prostate cancer by testosterone, even though no evidence to support this risk exists. Other possible risks include worsening symptoms of benign prostatic hypertrophy, liver toxicity, hyperviscosity, erythrocytosis, worsening untreated sleep apnea or severe heart failure. Despite this controversy, testosterone supplementation in the United States has increased substantially over the past several years. The physician should discuss with the patient the potential benefits and risks of TRT. The purpose of this review is to discuss what is known and not known regarding the benefits and risks of TRT. PMID:19707253

  4. Testosterone Replacement Therapy: The Emperor's New Clothes.

    PubMed

    Sansone, Andrea; Sansone, Massimiliano; Lenzi, Andrea; Romanelli, Francesco

    2017-02-01

    The mean age of the world population has steadily increased in the last decades, as a result of increased life expectancy and reduced birth rate. Global aging has led to a greater worldwide cost for healthcare: hormonal alterations contribute to the pathogenesis of several conditions and might cause a significant reduction in the perceived sense of well-being. Menopause is archetypal of hormonal alterations occurring during aging: in males, sex hormones do not decrease abruptly, yet testosterone levels decrease steadily and continuously during aging, ultimately resulting in late-onset hypogonadism. Treatment of this condition might mitigate most symptoms; however, testosterone replacement therapy (TRT) should be prescribed only in selected patients and it should not be considered as an antiaging treatment. In recent years, different authors have questioned health risks associated with testosterone treatment; while position statements from many scientific societies seem to be reassuring, the Food and Drug Administration has issued a warning in regard to the possible side effects of this therapy. We aim to review recent controversies and discoveries in regard to TRT.

  5. A microcosm study to support aquatic risk assessment of nickel: Community-level effects and comparison with bioavailability-normalized species sensitivity distributions.

    PubMed

    Hommen, Udo; Knopf, Burkhard; Rüdel, Heinz; Schäfers, Christoph; De Schamphelaere, Karel; Schlekat, Chris; Garman, Emily Rogevich

    2016-05-01

    The aquatic risk assessment for nickel (Ni) in the European Union is based on chronic species sensitivity distributions and the use of bioavailability models. To test whether a bioavailability-based safe threshold of Ni (the hazardous concentration for 5% of species [HC5]) is protective for aquatic communities, microcosms were exposed to 5 stable Ni treatments (6-96 μg/L) and a control for 4 mo to assess bioaccumulation and effects on phytoplankton, periphyton, zooplankton, and snails. Concentrations of Ni in the periphyton, macrophytes, and snails measured at the end of the exposure period increased in a dose-dependent manner but did not indicate biomagnification. Abundance of phytoplankton and snails decreased in 48 μg Ni/L and 96 μg Ni/L treatments, which may have indirectly affected the abundance of zooplankton and periphyton. Exposure up to 24 μg Ni/L had no adverse effects on algae and zooplankton, whereas the rate of population decline of the snails at 24 μg Ni/L was significantly higher than in the controls. Therefore, the study-specific overall no-observed-adverse-effect concentration (NOAEC) is 12 μg Ni/L. This NOAEC is approximately twice the HC5 derived from a chronic species sensitivity distribution considering the specific water chemistry of the microcosm by means of bioavailability models. Thus, the present study provides support to the protectiveness of the bioavailability-normalized HC5 for freshwater communities.

  6. Testosterone during Pregnancy and Gender Role Behavior of Preschool Children: A Longitudinal, Population Study.

    ERIC Educational Resources Information Center

    Hines, Melissa; Golombok, Susan; Rust, John; Johnston, Katie J.; Golding, Jean

    2002-01-01

    Related blood levels of testosterone and sex hormone-binding globulin in pregnant women to gender role behavior among 342 male and 337 female offspring at 3.5 years. Found that testosterone levels related linearly to girls' gender role behavior. Neither hormone related to boys' gender role behavior. Other factors, including older brothers or…

  7. Context matters: female aggression and testosterone in a year-round territorial neotropical songbird (Thryothorus leucotis).

    PubMed

    Gill, Sharon A; Alfson, Elizabeth D; Hau, Michaela

    2007-09-07

    Testosterone promotes aggressive behaviour in male vertebrates during the breeding season, but the importance of testosterone in female aggression remains unclear. Testosterone has both beneficial and detrimental effects on behaviour and physiology, prompting the hypothesis that selection favours an association between aggression and testosterone only in certain contexts in which intense or persistent aggression may be beneficial. We tested this hypothesis in a year-round territorial female buff-breasted wrens (Thryothorus leucotis), by exposing free-living females to experimental intrusions in different social (either single female or male, or paired decoys) and seasonal (pre-breeding or breeding) contexts. Females responded more aggressively to intrusions by females and pairs than to males. However, female intrusions elicited stronger responses during pre-breeding, whereas responses to pair intrusions were more intense during breeding. Territorial females had elevated testosterone levels after female intrusions and intermediate levels after pair intrusions during pre-breeding, but the levels of testosterone remained low after these intrusions during breeding. These results demonstrate seasonal differences in circulating testosterone following territorial aggression in female buff-breasted wrens and are suggestive of differences according to social context as well. Context-dependent elevation of testosterone implies that selection acts directly on female vertebrates to shape patterns of testosterone secretion.

  8. Testosterone stimulates glucose uptake and GLUT4 translocation through LKB1/AMPK signaling in 3T3-L1 adipocytes.

    PubMed

    Mitsuhashi, Kazuteru; Senmaru, Takafumi; Fukuda, Takuya; Yamazaki, Masahiro; Shinomiya, Katsuhiko; Ueno, Morio; Kinoshita, Shigeru; Kitawaki, Jo; Katsuyama, Masato; Tsujikawa, Muneo; Obayashi, Hiroshi; Nakamura, Naoto; Fukui, Michiaki

    2016-01-01

    Decreases in serum testosterone concentrations in aging men are associated with metabolic disorders. Testosterone has been reported to increase GLUT4-dependent glucose uptake in skeletal muscle cells and cardiomyocytes. However, studies on glucose uptake occurring in response to testosterone stimulation in adipocytes are currently not available. This study was designed to determine the effects of testosterone on glucose uptake in adipocytes. Glucose uptake was assessed with 2-[(3)H] deoxyglucose in 3T3-L1 adipocytes. GLUT4 translocation was evaluated in plasma membrane (PM) sheets and PM fractions by immunofluorescence and immunoblotting, respectively. Activation of GLUT4 translocation-related protein kinases, including Akt, AMPK, LKB1, CaMKI, CaMKII, and Cbl was followed by immunoblotting. Expression levels of androgen receptor (AR) mRNA and AR translocation to the PM were assessed by real-time RT-PCR and immunoblotting, respectively. The results showed that both high-dose (100 nM) testosterone and testosterone-BSA increased glucose uptake and GLUT4 translocation to the PM, independently of the intracellular AR. Testosterone and testosterone-BSA stimulated the phosphorylation of AMPK, LKB1, and CaMKII. The knockdown of LKB1 by siRNA attenuated testosterone- and testosterone-BSA-stimulated AMPK phosphorylation and glucose uptake. These results indicate that high-dose testosterone and testosterone-BSA increase GLUT4-dependent glucose uptake in 3T3-L1 adipocytes by inducing the LKB1/AMPK signaling pathway.

  9. Time for international action on treating testosterone deficiency syndrome

    PubMed Central

    Carruthers, Malcolm

    2009-01-01

    Aim Testosterone deficiency is having an increasing impact on men's health because of global aging, higher levels of obesity, diabetes and metabolic syndrome and adverse environmental factors such as stress xenoestrogens and anti-androgens. The question addressed is to what extent the large body of evidence on the benefits and safety of testosterone therapy is applied in clinical practice. Methods Demographic data for men over the age of 50 from different regions of the world have been compared with the number of men in that age group estimated from sales figures to be receiving testosterone treatment. Results On the basis of estimate that 20% of men over 50 in the general population of each region could be expected to have testosterone deficiency symptoms, on average only these men (0.69%) in most European countries were receiving treatment. Proportion was higher in the UK (1.00%) and Germany (1.89%), but lower in France (0.49%), Italy (0.51%) and Russia (0.54%). Interestingly, Australia had higher figures (1.64%), in spite of tight state control measures on androgen use. The USA has the highest treatment rate (7.96%) and this is increasing rapidly. If the basis for the diagnosis was the more conventional combination of symptoms plus biochemical evidence of low total and free testosterone levels, androgen deficiency would be expected in at least 5% of men over 50, and percentage treatment rates therefore four times higher. However, even on that basis, only in the USA do these exceed 10%. Conclusions International action is urgently needed to raise awareness in the medical profession in the various countries of these remarkably low levels of testosterone treatment. Improvement in this requires education and motivation of doctors and those regulating the healthcare systems. A public awareness campaign is needed to educate men about the symptoms of testosterone deficiency and its impact on their health. PMID:19326293

  10. Predicting low testosterone in aging men: a systematic review

    PubMed Central

    Millar, Adam C.; Lau, Adrian N.C.; Tomlinson, George; Kraguljac, Alan; Simel, David L.; Detsky, Allan S.; Lipscombe, Lorraine L.

    2016-01-01

    Background: Physicians diagnose and treat suspected hypogonadism in older men by extrapolating from the defined clinical entity of hypogonadism found in younger men. We conducted a systematic review to estimate the accuracy of clinical symptoms and signs for predicting low testosterone among aging men. Methods: We searched the MEDLINE and Embase databases (January 1966 to July 2014) for studies that compared clinical features with a measurement of serum testosterone in men. Three of the authors independently reviewed articles for inclusion, assessed quality and extracted data. Results: Among 6053 articles identified, 40 met the inclusion criteria. The prevalence of low testosterone ranged between 2% and 77%. Threshold testosterone levels used for reference standards also varied substantially. The summary likelihood ratio associated with decreased libido was 1.6 (95% confidence interval [CI] 1.3–1.9), and the likelihood ratio for absence of this finding was 0.72 (95% CI 0.58–0.85). The likelihood ratio associated with the presence of erectile dysfunction was 1.5 (95% CI 1.3–1.8) and with absence of erectile dysfunction was 0.83 (95% CI 0.76–0.91). Of the multiple-item instruments, the ANDROTEST showed both the most favourable positive likelihood ratio (range 1.9–2.2) and the most favourable negative likelihood ratio (range 0.37–0.49). Interpretation: We found weak correlation between signs, symptoms and testosterone levels, uncertainty about what threshold testosterone levels should be considered low for aging men and wide variation in estimated prevalence of the condition. It is therefore difficult to extrapolate the method of diagnosing pathologic hypogonadism in younger men to clinical decisions regarding age-related testosterone decline in aging men. PMID:27325129

  11. Testosterone, alcohol, and civil and rough conflict resolution strategies in lesbian couples.

    PubMed

    Baker, Lauren A; Pearcey, Sharon M; Dabbs, James M

    2002-01-01

    The present study investigated the relations among testosterone level, acute alcohol consumption, and the use of violent (Rough) or non-violent (Civil) conflict resolution strategies in lesbian couples. The participants were 54 lesbian campers at a women's campground or spectators at a gay pride celebration who each provided a saliva sample for testosterone assay and completed a questionnaire. On the questionnaire, participants indicated whether they used Civil or Rough tactics to deal with domestic discord, and whether or not their use of these tactics varied with their use of alcohol. High testosterone women used Rough tactics equally when drinking as when not drinking, while low testosterone women used Rough tactics far more often when drinking than when not drinking. Alcohol appears to release violent tenden- cies in low testosterone women, who are characteristically restrained under sober conditions, but has little effect on high testosterone women.

  12. Interest in Babies Negatively Predicts Testosterone Responses to Sexual Visual Stimuli Among Heterosexual Young Men.

    PubMed

    Zilioli, Samuele; Ponzi, Davide; Henry, Andrea; Kubicki, Konrad; Nickels, Nora; Wilson, M Claire; Maestripieri, Dario

    2016-01-01

    Men's testosterone may be an important physiological mechanism mediating motivational and behavioral aspects of the mating/parenting trade-off not only over time but also in terms of stable differences between mating-oriented and parenting-oriented individuals. In this study, we tested the hypothesis that self-reported interest in babies is inversely related to testosterone reactivity to cues of short-term mating among heterosexual young men. Among 100 participants, interest in babies was related to a slow life-history strategy, as assessed by the Mini-K questionnaire, and negatively related to testosterone responses to an erotic video. Interest in babies was not associated with baseline testosterone levels or with testosterone reactivity to nonsexual social stimuli. These results provide the first evidence that differential testosterone reactivity to sexual stimuli may be an important aspect of individual differences in life-history strategies among human males.

  13. Testosterone, thrombophilia, thrombosis.

    PubMed

    Glueck, Charles J; Friedman, Joel; Hafeez, Ahsan; Hassan, Atif; Wang, Ping

    2014-10-01

    We assessed previously undiagnosed thrombophilia-hypofibrinolysis in 11 testosterone (T)-taking men, five of whom developed deep venous thrombosis (DVT), four pulmonary embolism, one spinal cord infarction, and one osteonecrosis 3.5 months (median) after starting T gel (50-160 mg/day) or T intramuscular (50-250 mg/week). In the order of referral because of thrombosis after starting T, thrombophilia-hypofibrinolysis was studied in 11 men, and, separately, in two control groups without thrombosis - 44 healthy normal male controls and 39 healthy men taking T. Nine men had DVT or DVT-pulmonary embolism after 3.5 months (median) on T, one spinal cord infarction after 5 days on T, and one had osteonecrosis (knee and then hip osteonecrosis after 6 and 18 months on T). Four of the 11 men (36%) had high factor VIII (≥150%) vs. one of 42 (2%) controls (P = 0.005), and vs. one of 25 (4%) T-controls, (P = 0.023). Of the 11 men, two (18%) had factor V Leiden heterozygosity vs. none of 44 controls, (P = 0.04) and vs. none of 39 T-controls(P = 0.045). Of the 11 men, three had 4G4G plasminogen activator inhibitor-1 homozygosity, one prothrombin G20210A heterozygosity, one low protein S, and one high factor XI. When T was continued, second DVT-pulmonary embolism recurred in three of 11 men despite adequate anticoagulation. T interacts with thrombophilia-hypofibrinolysis leading to thrombosis. Men sustaining DVT-pulmonary embolism-osteonecrosis on T should be studied for thrombophilia. Continuation of T in thrombophilic men appears to be contraindicated because of recurrent thrombosis despite adequate anticoagulation. Before starting T, to prevent T-associated thrombosis, we recommend measures of factor V Leiden, factor VIII, and the prothrombin gene.

  14. Possible role of elevated serum testosterone in pathogenesis of renal stone formation

    PubMed Central

    Gupta, Kapil; Gill, Gurpreet Singh; Mahajan, Rajiv

    2016-01-01

    Background: Urolithiasis or renal stone formation occurs with three times higher frequency in males and decreases with age in parallel with the serum testosterone levels, suggesting a role played by male sex hormones. Androgens appear a promotion action and estrogens an inhibitory action on kidney stone formation in several animal models suggesting a study to be carried out to deduce the role played by serum testosterone in the formation of renal stones. Aim: The aim of this study is to define the involvement of serum total testosterone, free testosterone, and dihydrotestosterone in the pathogenesis of urolithiasis in males by comparing the results with healthy males with no present or past history of urolithiasis as controls. Materials and Methods: A case–control study was undertaken with 108 participants: 78 males diagnosed with urolithiasis and 30 age-matched healthy males. Results: The difference between mean age and body mass index of patients and controls were found to be nonsignificant. The total serum testosterone levels, serum dihydrotestosterone levels, were found to be higher in patients when compared to controls, and the difference was found to be significant. The levels of free testosterone and serum estradiol were also found to be higher in urolithiatic patients. Conclusion: The study demonstrates that elevated levels of serum testosterone and serum dihydrotestosterone might be involved in increased incidences of stone formation. The higher levels of estradiol do not seem to be a protective factor in males with urolithiasis with higher serum testosterone levels. PMID:27857889

  15. Testosterone deficiency: a historical perspective.

    PubMed

    Nieschlag, Eberhard; Nieschlag, Susan

    2014-01-01

    The biological effects of the testes and testosterone are known since antiquity. Aristotle knew the effects of castration and his hypothesis on fertilization is one of the first scientific encounters in reproductive biology. Over centuries, castration has been performed as punishment and to produce obedient slaves, but also to preserve the soprano voices of prepubertal boys. The Chinese imperial (and other oriental) courts employed castrates as overseers in harems who often obtained high-ranking political positions. The era of testis transplantation and organotherapy was initiated by John Hunter in London who transplanted testes into capons in 1786. The intention of his experiments was to prove the 'vital principle' as the basis for modern transplantation medicine, but Hunter did not consider endocrine aspects. Arnold Adolph Berthold postulated internal secretion from his testicular transplantation experiments in 1849 in Göttingen and is thus considered the father of endocrinology. Following his observations, testicular preparations were used for therapy, popularized by self-experiments by Charles-Edouard Brown-Séquard in Paris (1889), which can at best have placebo effects. In the 1920s Sergio Voronoff transplanted testes from animals to men, but their effectiveness was disproved. Today testicular transplantation is being refined by stem cell research and germ cell transplantation. Modern androgen therapy started in 1935 when Enrest Lacquer isolated testosterone from bull testes in Amsterdam. In the same year testosterone was chemically synthesized independently by Adolf Butenandt in Göttingen and Leopold Ruzicka in Basel. Since testosterone was ineffective orally it was either compressed into subcutaneous pellets or was used orally as 17α-methyl testosterone, now obsolete because of liver toxicity. The early phases of testosterone treatment coincide with the first description of the most prominent syndromes of hypogonadism by Klinefelter, by Kallmann, Del

  16. Testosterone deficiency: a historical perspective

    PubMed Central

    Nieschlag, Eberhard; Nieschlag, Susan

    2014-01-01

    The biological effects of the testes and testosterone are known since antiquity. Aristotle knew the effects of castration and his hypothesis on fertilization is one of the first scientific encounters in reproductive biology. Over centuries, castration has been performed as punishment and to produce obedient slaves, but also to preserve the soprano voices of prepubertal boys. The Chinese imperial (and other oriental) courts employed castrates as overseers in harems who often obtained high-ranking political positions. The era of testis transplantation and organotherapy was initiated by John Hunter in London who transplanted testes into capons in 1786. The intention of his experiments was to prove the ‘vital principle’ as the basis for modern transplantation medicine, but Hunter did not consider endocrine aspects. Arnold Adolph Berthold postulated internal secretion from his testicular transplantation experiments in 1849 in Göttingen and is thus considered the father of endocrinology. Following his observations, testicular preparations were used for therapy, popularized by self-experiments by Charles-Edouard Brown-Séquard in Paris (1889), which can at best have placebo effects. In the 1920s Sergio Voronoff transplanted testes from animals to men, but their effectiveness was disproved. Today testicular transplantation is being refined by stem cell research and germ cell transplantation. Modern androgen therapy started in 1935 when Enrest Lacquer isolated testosterone from bull testes in Amsterdam. In the same year testosterone was chemically synthesized independently by Adolf Butenandt in Göttingen and Leopold Ruzicka in Basel. Since testosterone was ineffective orally it was either compressed into subcutaneous pellets or was used orally as 17α-methyl testosterone, now obsolete because of liver toxicity. The early phases of testosterone treatment coincide with the first description of the most prominent syndromes of hypogonadism by Klinefelter, by Kallmann, Del

  17. Testosterone deficiency and quality of life in Australasian testicular cancer survivors: a prospective cohort study.

    PubMed

    O'Carrigan, B; Fournier, M; Olver, I N; Stockler, M R; Whitford, H; Toner, G C; Thomson, D B; Davis, I D; Hanning, F; Singhal, N; Underhill, C; Clingan, P; McDonald, A; Boland, A; Grimison, P

    2014-08-01

    This is the first prospective study in a contemporary Australian/New Zealand population to determine the prevalence of testosterone deficiency in testicular cancer survivors at 12 months from treatment, and any association with poorer quality of life. Hormone assays from 54 evaluable patients in a prospective cohort study revealed biochemical hypogonadism in 18 patients (33%) and low-normal testosterone in 13 patients (24%). We found no association between testosterone levels and quality of life (all P > 0.05). Hypogonadal patients should be considered for testosterone replacement to prevent long-term morbidity.

  18. Influence of testosterone gel treatment on spermatogenesis in men with hypogonadism.

    PubMed

    George, Mskhalaya; Yulia, Tishova; Svetlana, Kalinchenko

    2014-10-01

    The prevalence of androgen deficiency in reproductive-aged men is increasing and needs new approach to long-term hypogonadism treatment that can preserve fertility. An open non-controlled pilot study included 18 men with eugonadotropic hypogonadism, who received transdermal testosterone gel treatment for 3 months. Sperm analysis was made before treatment and after 3 month of testosterone therapy. Testosterone level was normalized in all patients, but no negative effect was observed on spermatogenesis. Testosterone gel therapy may be a therapy of choice in hypogonadal men of reproductive age but further studies are needed.

  19. Guns, testosterone, and aggression: an experimental test of a mediational hypothesis.

    PubMed

    Klinesmith, Jennifer; Kasser, Tim; McAndrew, Francis T

    2006-07-01

    We tested whether interacting with a gun increased testosterone levels and later aggressive behavior. Thirty male college students provided a saliva sample (for testosterone assay), interacted with either a gun or a children's toy for 15 min, and then provided another saliva sample. Next, subjects added as much hot sauce as they wanted to a cup of water they believed another subject would have to drink. Males who interacted with the gun showed significantly greater increases in testosterone and added more hot sauce to the water than did those who interacted with the children's toy. Moreover, increases in testosterone partially mediated the effects of interacting with the gun on this aggressive behavior.

  20. The Effects of Testosterone Supplementation on Cognitive Functioning in Older Men.

    PubMed

    Wahjoepramono, Eka J; Asih, Prita R; Aniwiyanti, Vilia; Taddei, Kevin; Dhaliwal, Satvinder S; Fuller, Stephanie J; Foster, Jonathan; Carruthers, Malcolm; Verdile, Giuseppe; Sohrabi, Hamid R; Martins, Ralph N

    2016-01-01

    Reduction in testosterone levels in men during aging is associated with cognitive decline and risk of dementia. Animal studies have shown benefits for testosterone supplementation in improving cognition and reducing Alzheimer's disease pathology. In a randomized, placebo-controlled, crossover study of men with subjective memory complaint and low testosterone levels, we investigated whether testosterone treatment significantly improved performance on various measures of cognitive functioning. Forty-four men were administered a battery of neuropsychological tests to establish the baseline prior to being randomly divided into two groups. The first group (Group A) received 24 weeks of testosterone treatment (T treatment) followed by 4 weeks washout, and then 24 weeks of placebo (P); the second group (Group B) received the same treatments, in reverse order (Placebo, washout, and then T treatment). In group A (TèP), compared to baseline, there was a modest (1 point) but significant improvement in general cognitive functioning as measured by the Mini Mental State Examination (MMSE) following testosterone treatment. This improvement from baseline was sustained following the washout period and crossover to placebo treatment. Similar Mini Mental State Examination (MMSE) scores were observed when comparing testosterone treatment with placebo. In group B (PèT) a significant increase was observed from baseline following testosterone treatment and a trend towards an increase when compared to placebo treatment. Improvements in baseline depression scores (assessed by Geriatric Depression Scale) were observed following testosterone/placebo treatment in both groups, and no difference was observed when comparing testosterone with placebo treatment. Our findings indicate a modest improvement on global cognition with testosterone treatment. Larger clinical trials with a longer follow- up and with the inclusion of blood and brain imaging markers are now needed to conclusively

  1. First case report of testosterone assay-interference in a female taking maca (Lepidium meyenii).

    PubMed

    Srikugan, L; Sankaralingam, A; McGowan, B

    2011-03-25

    A young female with prolonged intermenstrual bleeding was found to have raised total plasma testosterone of 25.8 nmol/l (NR<2.9 nmol/l) using the Roche Elecsys Testosterone I immunoassay without clinical features of virulisation. Few months ago investigations for lethargy and low libido had shown normal total testosterone of 0.8 nmol/l. Further history revealed that she was using maca extract to improve her lethargy and low libido. Maca is traditionally used for its aphrodisiac and fertility-enhancing properties. Maca use has not been shown to affect serum testosterone in mice and human studies. Immunoassay interference with maca was suspected. Testosterone immunoassays use monoclonal antibodies specifically directed against testosterone. They are prone to interference from androgenic compounds. Reanalysis of the original serum sample using Elecsys Testosterone II assay, a higher affinity assay, revealed a total testosterone level of 2.9 nmol/l. It is important to exclude assay interference when testosterone level is greater than 5 nmol/l without supportive clinical signs.

  2. First case report of testosterone assay-interference in a female taking maca (Lepidium meyenii)

    PubMed Central

    Srikugan, L; Sankaralingam, A; McGowan, B

    2011-01-01

    A young female with prolonged intermenstrual bleeding was found to have raised total plasma testosterone of 25.8 nmol/l (NR<2.9 nmol/l) using the Roche Elecsys Testosterone I immunoassay without clinical features of virulisation. Few months ago investigations for lethargy and low libido had shown normal total testosterone of 0.8 nmol/l. Further history revealed that she was using maca extract to improve her lethargy and low libido. Maca is traditionally used for its aphrodisiac and fertility-enhancing properties. Maca use has not been shown to affect serum testosterone in mice and human studies. Immunoassay interference with maca was suspected. Testosterone immunoassays use monoclonal antibodies specifically directed against testosterone. They are prone to interference from androgenic compounds. Reanalysis of the original serum sample using Elecsys Testosterone II assay, a higher affinity assay, revealed a total testosterone level of 2.9 nmol/l. It is important to exclude assay interference when testosterone level is greater than 5 nmol/l without supportive clinical signs. PMID:22700073

  3. The effects of castration followed testosterone supplementation in prostatic complex of Artibeus planirostris (Chiroptera: Phyllostomidae).

    PubMed

    Puga, Cíntia C I; Beguelini, Mateus R; Morielle-Versute, Eliana; Vilamaior, Patricia S L; Taboga, Sebastião R

    2016-06-01

    The prostatic complex (ventral and dorsal regions) of Artibeus planirostris exhibits seasonal variations throughout the year. Circulating testosterone was correlated with prostate weight, showing an increase from autumn to summer, with the highest peak in summer corresponding to the largest breeding season. This indicates that the level of serum testosterone influences variations in both testicular and prostatic weights. Serum testosterone levels seem to be closely related to the different responses of these glands throughout the year. The castration (consequent suppression of testosterone) and subsequent hormone supplementation may elucidate the relationship of these two glandular types with testosterone. Thus, the aim of this study was to evaluate the effect of castration and the testosterone supplementation in the male prostatic complex of A. planirostris. The results indicated that both prostatic regions were affected by the ablation of testosterone, presenting a decrease in cell proliferation and an increase in apoptosis. Similarly, the prostate was responsive to hormonal supplementation, having a recovery of the active morphophysiological pattern with testosterone supplementation. However, data have shown that the ventral region was more sensitive to changes in testosterone than the dorsal, presenting greater cell renewal.

  4. Testosterone and social evaluative stress: the moderating role of basal cortisol.

    PubMed

    Bedgood, Deidra; Boggiano, Mary M; Turan, Bulent

    2014-09-01

    Research has suggested that stressful situations lead to a decrease in testosterone, whereas concern with one's social status increases testosterone. However, results from studies examining testosterone reactivity in stressful situations that involve evaluation by others (hence status concerns) are inconsistent. Furthermore, there is a lack of research examining individual differences in testosterone responses in such situations. In this study 85 male participants underwent the Trier Social Stress Test (TSST, which includes performing speech and arithmetic tasks in front of two critical evaluators) and practiced solving puzzles. Testosterone and cortisol levels were assessed from saliva. Across participants, testosterone increased from baseline to peak levels following the stressor tasks. Importantly, the increase in testosterone was larger for participants with lower basal cortisol. Hence, lower basal cortisol (which is known to be associated with low social fearfulness) may help one to mobilize a larger testosterone response in situations that involve social-evaluative stress. Given the hypothesized adaptive role of a larger testosterone response in social competition situations, the results suggest that there may be long-term benefits in learning to lower one's social fearfulness in situations involving potential for negative evaluation by others.

  5. Male rats secrete luteinizing hormone and testosterone episodically.

    PubMed

    Ellis, G B; Desjardins, C

    1982-05-01

    We studied the temporal aspects of endocrine signaling between the pituitary gland and testes by measuring moment to moment changes in blood LH and testosterone levels in individual male rats. Each rat was fitted with an indwelling vascular cannula, and blood was withdrawn every 5 min for 8-12 h. Rats were maintained throughout the intensive blood-sampling period with an isotonic blood replacement mixture containing rat red blood cells and a human plasma protein preparation. LH and testosterone measurements were made in plasma volumes of 50 and 60 microliters. Most rats released LH in well defined pulses, characterized by a rapid increase in plasma LH within 5-10 min and a gradual decline lasting for the next 50-70 min. LH pulses occurred singly or in trains of two to four. Episodes of testosterone secretion spanned 3-6 h and were marked by a slowly graded rise and fall of plasma testosterone. In several instances, testosterone episodes were preceded (1-2 h) by a train of closely coupled LH pulses. Within a particular animal on different days, hormone episodes varied in number, amplitude, and timing. A particular hormone profile did not serve as a reliable hormone signature for an individual rat. Many rats displayed a characteristic sequence of 1) multiple LH pulses, 2) a sustained testosterone episode, and 3) a period of no LH pulses. This tripartite sequence of events is viewed as the essence of pituitary-testicular stimulation, and testicular negative feedback. Intermittent, short term fluctuations in peripheral levels of LH and testosterone represent the blood-borne, gland to gland signals controlling hypothalamic-pituitary-testicular function in the normal rat.

  6. Women's Preference for Attractive Makeup Tracks Changes in Their Salivary Testosterone.

    PubMed

    Fisher, Claire I; Hahn, Amanda C; DeBruine, Lisa M; Jones, Benedict C

    2015-12-01

    Previous research suggests that women's motivation to appear attractive is increased around the time of ovulation. However, the specific hormonal correlates of within-woman changes in motivation to appear attractive have not been investigated. To address this issue, we used a longitudinal design and a data-driven visual preference task. We found that women's preference for attractive makeup increases when their salivary testosterone levels are high. The relationship between testosterone level and preference for attractive makeup was independent of estradiol level, progesterone level, and estradiol-to-progesterone ratio. These results suggest that testosterone may contribute to changes in women's motivation to wear attractive makeup and, potentially, their motivation to appear attractive in general. Our results are also consistent with recent models of the role of testosterone in social behavior, according to which testosterone increases the probability of behaviors that could function to support the acquisition of mates and competition for resources.

  7. Testosterone and Haemosporidian Parasites Along a Tropical Elevational Gradient in Rufous-Collared Sparrows (Zonotrichia capensis).

    PubMed

    Escallón, Camilo; Weinstein, Nicole M; Tallant, James A; Wojtenek, Winfried; Rodríguez-Saltos, Carlos A; Bonaccorso, Elisa; Moore, Ignacio T

    2016-10-01

    Elevation has been proposed as a dominant ecological variable shaping life history traits and subsequently their underlying hormonal mechanisms. In an earlier meta-analysis of tropical birds, elevation was positively related to testosterone levels. Furthermore, parasitism by avian haemosporidians should vary with elevation as environmental conditions affect vector abundance, and while testosterone is needed for breeding, it is hypothesized to be immunosuppressive and thus could exacerbate haemosporidian infection. Our objective in this study was to examine the relationships between elevation, testosterone levels, and parasitism by avian haemosporidians. We surveyed breeding male rufous-collared sparrows (Zonotrichia capensis) across a wide elevational range along the equator. We measured baseline testosterone levels, haemosporidian infection at four elevations spanning the species' natural range in the Ecuadorian Andes (600, 1500, 2100, 3300 m). Testosterone levels from breeding males were not related to elevation, but there was high intrapopulation variability. Testosterone levels were not related to the probability of parasitism, but our results from one population suggested that the likelihood of being infected by haemosporidian parasites was greater when in breeding condition. In conclusion, even though there is variation in life history strategies among the studied populations, wider divergence in seasonality and life history traits would probably be needed to detect an effect of elevation on testosterone if one exists. Additionally, our results show that variation in testosterone is not related to infection risk of haemosporidians, thus other factors that take a toll on energetic resources, such as reproduction, should be looked at more closely.

  8. Testosterone regulates metabolism of plasma chylomicrons in rats

    SciTech Connect

    Staprans, I.; Rapp, J.H.; Pan, X.M.; Ong, D.L.; Feingold, K.R. )

    1990-07-01

    Previously we demonstrated a marked sex difference in the metabolism of chylomicrons in adult rats. In males, radiolabeled chylomicrons displayed a longer dwell time on endothelial surfaces, which resulted in a decreased chylomicron uptake by the liver. The increased rate of chylomicron metabolism in females was associated with increased postheparin lipoprotein lipase activity. In the present study, we have investigated the effects of physiological doses of sex steroid hormones on the metabolism of chylomicrons and postheparin lipoprotein lipase activity. No sex differences were found in prepubertal animals. We also found no difference in chylomicron metabolism in control female, castrated female, estrogen-treated female, castrated male, and estrogen-treated male rats. However, control male, testosterone-treated male, and testosterone-treated female rats showed increased endothelial binding of chylomicrons and decreased chylomicron uptake by the liver. Postheparin lipoprotein lipase activity also was decreased by testosterone administration. In parallel with the alterations in chylomicron metabolism, serum high density lipoprotein levels in male rats decreased with testosterone administration. These results indicate that the differences in chylomicron metabolism, postheparin lipoprotein lipase activities, and serum high density lipoprotein levels observed between male and female rats are due to testosterone.

  9. Recent topics related to testosterone deficiency syndrome in Japan

    PubMed Central

    Tsujimura, Akira; Nonomura, Norio

    2011-01-01

    Androgens, the levels of which decrease with ageing, play many physiological roles in various organs. Testosterone deficiency syndrome (TDS) has received widespread attention in the last several years. First-line treatment for TDS should be testosterone replacement therapy (TRT), which is reported to improve several TDS symptoms. Recently, a clinical practice manual for TDS was written and published by a collaborative team from the Japanese Urological Association and the Japanese Society for the Study of the Aging Male to recommend standard procedures for the diagnosis, treatment, prevention and monitoring of adverse reactions to TRT and for post-treatment assessment. In this manual, intramuscular injection of testosterone enanthate or human chorionic gonadotropin and the testosterone gel ‘Glowmin' were recommended as TRT. Currently, two topics related to TDS are being focused on in Japan: the relationship between TDS and metabolic syndrome and treatment options for eugonadal patients with TDS symptoms. In this review, the possibility of TRT for metabolic syndrome as well as the relationship between testosterone and adiponectin, which is a key molecule in metabolic syndrome, is discussed. Finally, the possibility of herbal medicines as a treatment option for patients with TDS is addressed, especially for eugonadal patients, because eugonadal men with TDS symptoms account for approximately 30% of the general population. The increase in the levels of several cytokines, such as IL-8, IL-13, interferon-γ and tumor necrosis factor-α, after herbal medicine treatment may be the reason for this efficacy. PMID:21460860

  10. Second-to-Fourth Digit Length, Testosterone and Spatial Ability

    ERIC Educational Resources Information Center

    Kempel, P.; Gohlke, B.; Klempau, J.; Zinsberger, P.; Reuter, M.; Hennig, J.

    2005-01-01

    Based on stimulating findings suggesting that prenatal levels of steroids may influence cognitive functions, a study with N=40 healthy volunteers of both sexes was conducted. Prenatal levels of testosterone (T) were estimated by use of the second-to-fourth digit ratio (2D:4D) which is supposed to be controlled by the same genes involved in…

  11. Testosterone replacement in older men and women.

    PubMed

    Morley, J E

    2001-01-01

    This article examines in detail the present state of the art concerning androgen deficiency in aging males. There is increasing evidence that testosterone replacement in hypogonadal older males can result in an improvement in quality of life. The major effects of testosterone are on libido, muscles, bone, and cognition. Less information is available concerning the role of testosterone in postmenopausal women, but testosterone replacement may have a role to play in treating disorders of libido and the sarcopenia that occurs at menopause.

  12. Single dose testosterone administration alleviates gaze avoidance in women with Social Anxiety Disorder.

    PubMed

    Enter, Dorien; Terburg, David; Harrewijn, Anita; Spinhoven, Philip; Roelofs, Karin

    2016-01-01

    Gaze avoidance is one of the most characteristic and persistent social features in people with Social Anxiety Disorder (SAD). It signals social submissiveness and hampers adequate social interactions. Patients with SAD typically show reduced testosterone levels, a hormone that facilitates socially dominant gaze behavior. Therefore we tested as a proof of principle whether single dose testosterone administration can reduce gaze avoidance in SAD. In a double-blind, within-subject design, 18 medication-free female participants with SAD and 19 female healthy control participants received a single dose of 0.5mg testosterone and a matched placebo, at two separate days. On each day, their spontaneous gaze behavior was recorded using eye-tracking, while they looked at angry, happy, and neutral facial expressions. Testosterone enhanced the percentage of first fixations to the eye-region in participants with SAD compared to healthy controls. In addition, SAD patients' initial gaze avoidance in the placebo condition was associated with more severe social anxiety symptoms and this relation was no longer present after testosterone administration. These findings indicate that single dose testosterone administration can alleviate gaze avoidance in SAD. They support theories on the dominance enhancing effects of testosterone and extend those by showing that effects are particularly strong in individuals featured by socially submissive behavior. The finding that this core characteristic of SAD can be directly influenced by single dose testosterone administration calls for future inquiry into the clinical utility of testosterone in the treatment of SAD.

  13. Changes in saliva testosterone after psychological stimulation in men.

    PubMed

    Hellhammer, D H; Hubert, W; Schürmeyer, T

    1985-01-01

    Saliva testosterone (ST) concentration was measured in 20 young adult and healthy men before, during and after the presentation of five different films. The films were selected to provoke erotic, sexual, aggressive, stressful and neutral stimulation, respectively. An increase in ST was found 15 min after the onset of both the erotic and the sexual stimulation, while a decline of ST levels was observed during the stressful movie showing dental surgery. No changes were found for either the neutral or the aggressive stimulant. Furthermore, no differences were found between ST levels before and after the showing of any of the films. Thus, saliva testosterone responds quickly to psychological stimulation, and may provide a practical alternative to testosterone measurements in serum under psychological test situations.

  14. Testosterone replacement in the infertile man

    PubMed Central

    Sabanegh, Edmund

    2016-01-01

    Hypogonadism is a common clinical condition affecting men of different age groups. In addition to its sexual consequences, it has several implications posing significant concerns for a man’s health and well-being. Recent advances in testosterone (T) supplementation have facilitated hypogonadism treatment. Despite that, patients complaining of infertility or seeking conception are still hindered by the unfavorable effects supplemental T has on testicular function. Consequently, alternative approaches that can stimulate endogenous T production are favored. Selective estrogen receptor modulators, gonadotropins and aromatase inhibitors (AIs) can be successful in restoring serum T levels, preserving fertility, and providing symptomatic relief. PMID:28078217

  15. Experimental increase of testosterone increases boldness and decreases anxiety in male African striped mouse helpers.

    PubMed

    Raynaud, Julien; Schradin, Carsten

    2014-04-22

    Males of many species can adjust their behaviors to environmental conditions by changing reproductive tactics. Testosterone surges in adult breeding males typically inhibit the expression of paternal care while facilitating the expression of aggression during environmental changes. Similarly, in non-breeding philopatric males of cooperatively breeding species, up-regulation of testosterone may inhibit alloparental care while facilitating dispersal, i.e. males might become bolder and more explorative. We tested this hypothesis in philopatric male African striped mice, Rhabdomys pumilio. Striped mouse males can either remain in their natal groups providing alloparental care or they can disperse seeking mating opportunities. Compared to philopatric males, dispersed males typically show higher testosterone levels and lower corticosterone levels, and more aggression toward pups and same sex conspecifics. We experimentally increased the testosterone levels of the philopatric males kept in their family groups when pups were present. Testosterone-treated males did not differ significantly from control males in alloparental care and in aggression toward same-sex conspecifics. Compared to the control males, testosterone treated males were bolder, more active, and less anxious; they also showed lower corticosterone levels. The philopatric males were sensitive to our testosterone treatment for dispersal- and anxiety-like behavior but insensitive for social behaviors. Our results suggest a role of testosterone in dispersal.

  16. Gender-Typed Play and Amniotic Testosterone

    ERIC Educational Resources Information Center

    Knickmeyer, Rebecca Christine; Wheelwright, Sally; Taylor, Kevin; Raggatt, Peter; Hackett, Gerald; Baron-Cohen, Simon

    2005-01-01

    Sex differences in play are apparent in a number of mammalian species, including humans. Prenatal testosterone may contribute to these differences. The authors report the first attempt to correlate gender-typed play in a normative sample of humans with measurements of amniotic testosterone (aT). Testosterone was measured in the amniotic fluid of…

  17. Testosterone vs. aromatase inhibitor in older men with low testosterone: effects on cardiometabolic parameters.

    PubMed

    Dias, J P; Shardell, M D; Carlson, O D; Melvin, D; Caturegli, G; Ferrucci, L; Chia, C W; Egan, J M; Basaria, S

    2017-01-01

    Testosterone (T) replacement is being increasingly offered to older men with age-related decline in testosterone levels. The effects of long-term testosterone replacement and aromatase inhibition (AI) on glucose homeostasis and cardiometabolic markers were determine in older non-diabetic men with low testosterone levels. Men ≥65 years, mean age 71 ± 3 years with serum total T < 350 ng/dL were randomized in a double-blind, placebo-controlled, parallel-group, proof-of-concept trial evaluating the effects of 5 g transdermal testosterone gel (TT) (n = 10), 1 mg anastrozole (n = 10) or placebo (n = 9) daily for 12 months. Homeostatic Model Assessment of insulin resistance (HOMAIR ) was the primary outcome. Secondary outcomes included OGIS in response to OGTT, fasting lipids, C-reactive protein (CRP), adipokines, and abdominal and mid-thigh fat by computed tomography. All outcomes were assessed at baseline and 12 months. After 12 months, absolute changes in HOMAIR in both treatment arms (TT group: -0.05 ± 0.21); (AI group: 0.15 ± 0.10) were similar to placebo (-0.11 ± 0.26), as were CRP and fasting lipid levels. Adiponectin levels significantly decreased in the TT group (-1.8 ± 0.9 mg/L, p = 0.02) and abdominal subcutaneous fat (-60.34 ± 3.19 cm(2) , p = 0.003) and leptin levels (-1.5 ± 1.2 ng/mL, p = 0.04) were significantly lower with AI. Mid-thigh subcutaneous fat was reduced in both treatment arms (TT group: -4.88 ± 1.24 cm(2) , p = 0.008); (AI group: -6.05 ± 0.87 cm(2) , p = 0.0002). In summary, in this proof-of-concept trial, changes in HOMAIR AI were similar in all three groups while the effects of intervention on subcutaneous fat distribution and adipokines were variable. Larger efficacy and safety trials are needed before AI pharmacotherapy can be considered as a treatment option for low T levels in older men.

  18. Is Testosterone Deficiency A Possible Risk Factor For Priapism Associated With Sickle Cell Disease?

    PubMed Central

    Morrison, Belinda F.; Anele, Uzoma A.; Reid, Marvin E.; Madden, Wendy A.; Feng, Zhaoyong; Burnett, Arthur L.

    2015-01-01

    Purpose The purpose of this study was to determine the association of testosterone deficiency and priapism in adult men with SCD. Methods A cross-sectional study of 50 adult men with homozygous S SCD was performed. All patients had early morning blood taken for total and free testosterone, FSH, LH, prolactin, lipid levels, LDH and hematological indices. Patients completed an interviewer-administered questionnaire regarding priapism frequency, duration, and treatment. Testosterone deficiency was defined as a serum total testosterone < 12 nmol/L (346 ng/dl). Results The mean age of the study population was 34.2 ± 8.9 years. Priapism was noted in 24 (48%) patients and was most frequently seen in men between ages 18–25 years. Testosterone deficiency was observed in 11 of 50 (22 %) of all patients, and particularly in 6 of 24 (25%) patients with histories of priapism. There was no difference in mean total testosterone levels in patients with and without a history of priapism (16.7± 4.9 nmol/L and 15.4±5.9 nmol/L, respectively) (p=0.43). Similarly, there was no difference in serum LH and FSH levels based on history of priapism. Conclusion Testosterone deficiency is prevalent in patients with SCD; however, we did not identify an association based on a history of priapism. Larger, prospectively gathered data is needed to define the priapism profile of SCD patients with testosterone deficiency. PMID:25371242

  19. Effect of testosterone therapy on the female voice

    PubMed Central

    Glaser, R.; York, A.; Dimitrakakis, C.

    2016-01-01

    Abstract Objectives This prospective study was designed to investigate the effect of testosterone, delivered by subcutaneous implants, on the female voice. Methods Ten women who had opted for testosterone therapy were recruited for voice analysis. Voices were recorded prior to treatment and at 3 months, 6 months, and 12 months while on testosterone therapy. Acoustic samples were collected with subjects reading a sentence, reading a paragraph, and participating in a conversation. Significant changes in the voice over time were investigated using a repeated-measures analysis of variance with the fundamental frequency (F 0) as a response variable. Demographic variables associated with characteristics of the voice were assessed. Results There were no significant differences in average F 0 related to smoking history, menopausal status, weight, or body mass index. There was no difference in average fundamental speaking frequency (sentence, paragraph, conversation) between the pre-treatment group and any post-treatment group at 3 and 12 months. There was an increase in sentence speech F 0 at 6 months. Two of three patients with lower than expected F 0 at baseline improved on testosterone therapy. Conclusion Therapeutic levels of testosterone, delivered by subcutaneous implant, had no adverse affect on the female voice including lowering or deepening of the voice. PMID:26857354

  20. Testosterone-secreting adrenal adenoma in a peripubertal girl

    SciTech Connect

    Kamilaris, T.C.; DeBold, C.R.; Manolas, K.J.; Hoursanidis, A.; Panageas, S.; Yiannatos, J.

    1987-11-13

    A 15-year-old girl who presented with primary amenorrhea and virilization had an adrenocortical adenoma that secreted predominantly testosterone. To the authors' knowledge, she is the first peripubertal and second youngest patient with a testosterone-secreting adrenal tumor described. Serum dehydroepiandrosterone sulfate and urinary 17-ketosteroid an 17-hydroxycorticosteroid levels were normal. A tumor was located by a computed tomographic (CT) scan and by uptake of 6-..beta..-(/sup 75/Se) selenomethylnorcholesterol. Microscopic examination of the tumor showed typical features of an adrenocortical adenoma with no histologic features characteristic of Leydig cells. Postoperatively, her hirsutism regressed, she rapidly went through puberty, and regular monthly menstruation started four months later. Finding the source of testosterone in a virilized patient can be difficult. Eleven of the 14 previously described patients with testosterone-secreting adrenal tumors initially underwent misdirected surgery on the ovaries. Review of these cases revealed that results of hormone stimulation and suppression tests are unreliable and that these tumors are usually large. Therefore, CT scanning of the adrenal glands is recommended in all patients suspected of having a testosterone-secreting tumor.

  1. Testosterone related to age and life-history stages in male baboons and geladas

    PubMed Central

    Beehner, Jacinta C.; Gesquiere, Laurence; Seyfarth, Robert M.; Cheney, Dorothy L.; Alberts, Susan C.; Altmann, Jeanne

    2013-01-01

    Despite significant advances in our knowledge of how testosterone mediates life-history trade-offs, this research has primarily focused on seasonal species. We know comparatively little about the relationship between testosterone and life-history stages for non-seasonally breeding species. Here we examine testosterone profiles across the lifespan of males from three non-seasonally breeding primates: yellow baboons (Papio cynocephalus or P. hamadryas cynocephalus), chacma baboons (Papio ursinus or P. h. ursinus), and geladas (Theropithecus gelada). First, we predict that testosterone profiles will track the reproductive profiles of each taxon across their respective breeding years. Second, we evaluate age-related changes in testosterone to determine whether several life-history transitions are associated with these changes. Subjects include males (>2.5 years) from wild populations of each taxon from whom we had fecal samples for hormone determination. Although testosterone profiles across species were broadly similar, considerable variability was found in the timing of two major changes: (1) the attainment of adult levels of testosterone, and (2) the decline in testosterone after the period of maximum production. Attainment of adult testosterone levels was delayed by one year in chacmas compared with yellows and geladas. With respect to the decline in testosterone, geladas and chacmas exhibited a significant drop after three years of maximum production, while yellows declined so gradually that no significant annual drop was ever detected. For both yellows and chacmas, increases in testosterone production preceded elevations in social dominance rank. We discuss these differences in the context of ecological and behavioral differences exhibited by these taxa. PMID:19712676

  2. Sex-specific associations of testosterone with prefrontal-hippocampal development and executive function.

    PubMed

    Nguyen, Tuong-Vi; Lew, Jimin; Albaugh, Matthew D; Botteron, Kelly N; Hudziak, James J; Fonov, Vladimir S; Collins, D Louis; Ducharme, Simon; McCracken, James T

    2017-02-01

    Testosterone is thought to play a crucial role in mediating sexual differentiation of brain structures. Examinations of the cognitive effects of testosterone have also shown beneficial and potentially sex-specific effects on executive function and mnemonic processes. Yet these findings remain limited by an incomplete understanding of the critical timing and brain regions most affected by testosterone, the lack of documented links between testosterone-related structural brain changes and cognition, and the difficulty in distinguishing the effects of testosterone from those of related sex steroids such as of estradiol and dehydroepiandrosterone (DHEA). Here we examined associations between testosterone, cortico-hippocampal structural covariance, executive function (Behavior Rating Inventory of Executive Function) and verbal memory (California Verbal Learning Test-Children's Version), in a longitudinal sample of typically developing children and adolescents 6-22 yo, controlling for the effects of estradiol, DHEA, pubertal stage, collection time, age, handedness, and total brain volume. We found prefrontal-hippocampal covariance to vary as a function of testosterone levels, but only in boys. Boys also showed a specific association between positive prefrontal-hippocampal covariance (as seen at higher testosterone levels) and lower performance on specific components of executive function (monitoring the action process and flexibly shifting between actions). We also found the association between testosterone and a specific aspect of executive function (monitoring) to be significantly mediated by prefrontal-hippocampal structural covariance. There were no significant associations between testosterone-related cortico-hippocampal covariance and verbal memory. Taken together, these findings highlight the developmental importance of testosterone in supporting sexual differentiation of the brain and sex-specific executive function.

  3. Arsenic Bioavailability, Bioaccessibility, And Speciation

    EPA Science Inventory

    The term bioavailability has many different meanings across various disciplines. Often bioavailability is concerned with human health aspects such as the case of urban children interacting with contaminated soil. The still utilized approach to base risk assessment on total meta...

  4. Testosterone Induces Increase in Aquaporin (AQP)-1, 5, and 7 Expressions in the Uteri of Ovariectomized Rats.

    PubMed

    Salleh, Naguib; Mokhtar, Helmy Mohd; Kassim, Normadiah M; Giribabu, Nelli

    2015-12-01

    Testosterone has been reported to cause a decrease in uterine fluid volume in which this could involve the aquaporins (AQPs). This study aimed to investigate effect of testosterone on uterine AQP-1, 5, and 7 expressions in order to explain the reported reduction in uterine fluid volume under testosterone influence. Ovariectomized adult female rats received peanut oil, testosterone (1 mg/kg/day), estrogen (0.2 µg/kg/day), or combined estrogen plus testosterone for three consecutive days. Other groups received 3 days estrogen followed by 2 days either peanut oil or testosterone with or without flutamide or finasteride. A day after last injection, uteri were harvested, and the levels of AQP-1, 5, and 7 messenger RNA (mRNA) in uterine tissue homogenates were analyzed by real-time PCR (qPCR). Distributions of AQP-1, 5, and 7 proteins in uterus were observed by immunofluorescence. Levels of AQP-1 mRNA were elevated in rats receiving either estrogen or testosterone-only treatment; however, levels of AQP-5 and 7 mRNAs were elevated in rats receiving testosterone-only treatment. In rats pre-treated with estrogen, testosterone treatment resulted in higher AQP-1, 5, and 7 mRNA levels compared to vehicle treatment. Testosterone effects were antagonized by flutamide but not finasteride. Immunofluorescence study showed that AQP-1 was highly distributed in uterine lumenal epithelium following estrogen or testosterone-only treatment. However, AQP-5 and 7 distributions were high in uterine lumenal epithelium following testosterone-only treatment. Testosterone-induced up-regulation of AQP-1, 5, and 7 expressions in uterus could explain the observed reduction in uterine fluid volume as reported under this condition.

  5. Thermodynamically Correct Bioavailability Estimations

    DTIC Science & Technology

    1992-04-30

    6448 I 1. SWPPUMENTA* NOTIS lIa. OISTUAMJTiOAVAILAIILTY STATIMENT 121 OT REbT ostwosCo z I Approved for public release; distribution unlimited... research is to develop thermodynamically correct bioavailability estimations using chromatographic stationary phases as a model of the "interphase

  6. Low testosterone correlates with delayed development in male orangutans.

    PubMed

    Emery Thompson, Melissa; Zhou, Amy; Knott, Cheryl D

    2012-01-01

    Male orangutans (Pongo spp.) display an unusual characteristic for mammals in that some adult males advance quickly to full secondary sexual development while others can remain in an adolescent-like form for a decade or more past the age of sexual maturity. Remarkably little is understood about how and why differences in developmental timing occur. While fully-developed males are known to produce higher androgen levels than arrested males, the longer-term role of steroid hormones in male life history variation has not been examined. We examined variation in testosterone and cortisol production among 18 fully-developed ("flanged") male orangutans in U.S. captive facilities. Our study revealed that while testosterone levels did not vary significantly according to current age, housing condition, and species origin, males that had undergone precocious development had higher testosterone levels than males that had experienced developmental arrest. While androgen variation had previously been viewed as a state-dependent characteristic of male developmental status, our study reveals that differences in the physiology of early and late developing males are detectable long past the developmental transition and may instead be trait-level characteristics associated with a male's life history strategy. Further studies are needed to determine how early in life differences in testosterone levels emerge and what consequences this variation may have for male behavioral strategies.

  7. Low Testosterone Correlates with Delayed Development in Male Orangutans

    PubMed Central

    Emery Thompson, Melissa; Zhou, Amy; Knott, Cheryl D.

    2012-01-01

    Male orangutans (Pongo spp.) display an unusual characteristic for mammals in that some adult males advance quickly to full secondary sexual development while others can remain in an adolescent-like form for a decade or more past the age of sexual maturity. Remarkably little is understood about how and why differences in developmental timing occur. While fully-developed males are known to produce higher androgen levels than arrested males, the longer-term role of steroid hormones in male life history variation has not been examined. We examined variation in testosterone and cortisol production among 18 fully-developed (“flanged”) male orangutans in U.S. captive facilities. Our study revealed that while testosterone levels did not vary significantly according to current age, housing condition, and species origin, males that had undergone precocious development had higher testosterone levels than males that had experienced developmental arrest. While androgen variation had previously been viewed as a state-dependent characteristic of male developmental status, our study reveals that differences in the physiology of early and late developing males are detectable long past the developmental transition and may instead be trait-level characteristics associated with a male’s life history strategy. Further studies are needed to determine how early in life differences in testosterone levels emerge and what consequences this variation may have for male behavioral strategies. PMID:23077585

  8. Salivary Testosterone Levels and Health Status in Men and Women in the British General Population: Findings from the Third National Survey of Sexual Attitudes and Lifestyles (Natsal-3)

    PubMed Central

    Macdowall, W.; Copas, A. J.; Tanton, C.; Keevil, B. G.; Lee, D. M.; Mitchell, K. R.; Field, N.; Sonnenberg, P.; Bancroft, J.; Mercer, C. H.; Wallace, A. M.; Johnson, A. M.; Wellings, K.; Wu, F. C. W.

    2016-01-01

    Context: Salivary T (Sal-T) measurement by liquid chromatography–tandem mass spectroscopy resents the opportunity to examine health correlates of Sal-T in a large-scale population survey. Objective: This study sought to examine associations between Sal-T and health-related factors in men and women age 18–74 years. Design and Setting: Morning saliva samples were obtained from participants in a cross-sectional probability-sample survey of the general British population (Natsal-3). Self-reported health and lifestyle questions were administered as part of a wider sexual health interview. Participants: Study participants included 1599 men and 2123 women. Methods: Sal-T was measured using liquid chromatography–tandem mass spectroscopy. Linear regression was used to examine associations between health factors and mean Sal-T. Results: In men, mean Sal-T was associated with a range of health factors after age adjustment, and showed a strong independent negative association with body mass index (BMI) in multivariable analysis. Men reporting cardiovascular disease or currently taking medication for depression had lower age-adjusted Sal-T, although there was no association with cardiovascular disease after adjustment for BMI. The decline in Sal-T with increasing age remained after adjustment for health-related factors. In women, Sal-T declined with increasing age; however, there were no age-independent associations with health-related factors or specific heath conditions with the exception of higher Sal-T in smokers. Conclusions: Sal-T levels were associated, independently of age, with a range of self-reported health markers, particularly BMI, in men but not women. The findings support the view that there is an age-related decline in Sal-T in men and women, which cannot be explained by an increase in ill health. Our results demonstrate the potential of Sal-T as a convenient measure of tissue androgen exposure for population research. PMID:27552539

  9. Pharmacokinetics of gestodene and ethinylestradiol in 14 women during three months of treatment with a new tri-step combination oral contraceptive: serum protein binding of gestodene and influence of treatment on free and total testosterone levels in the serum.

    PubMed

    Kuhnz, W; Baumann, A; Staks, T; Dibbelt, L; Knuppen, R; Jütting, G

    1993-10-01

    The pharmacokinetics of gestodene (GEST) and ethinylestradiol (EE2) were determined in 14 healthy women (age 18 to 32 years) during a treatment period of three months with a new tri-step combination oral contraceptive (Milvane). Prior to this treatment period, the same women received a single administration of a coated tablet containing 0.1 mg GEST together with 0.03 mg EE2. There was a wash-out phase of one week between both treatments. Following single dose administration, a mean terminal half-life of 18 h was observed for GEST. The total clearance was 0.9 ml x min-1 x kg-1 and the volume of distribution was 84 l. During a treatment cycle, GEST levels in the serum accumulated by a factor of 8 as compared to single dose administration. Steady-state drug levels were reached during the second half of each cycle. As compared to single dose administration, the following changes were observed for GEST at the end of treatment cycles one and three: prolonged terminal half-life (20 to 22 h), reduced total (0.16 ml x min-1 x kg-1) and free clearance (ca. 27 ml x min-1 x kg-1), reduced volume of distribution (ca. 18 l). A concomitant EE2-induced increase in the SHBG concentrations by a factor of three as compared to pretreatment values was observed during a treatment cycle and appeared to be mainly responsible for the changes in the pharmacokinetics of GEST. Marked changes were also seen for the serum protein binding of GEST. After single dose administration, the free fraction of GEST was 1.3% and the fractions bound to SHBG and albumin were 69.4% and 29.3%, respectively. At the end of cycle one, the free fraction was only 0.6% and the fractions bound to SHBG and albumin were 81.4% and 18.0%, respectively. There was no difference in corresponding pharmacokinetic parameters and in the serum protein binding of GEST at the end of cycles one and three. On the last day of treatment cycles one and three, the AUC(0-4h) values of EE2 were 299.2 and 278.1 pg x ml-1 x h, respectively

  10. IQ, Fetal Testosterone and Individual Variability in Children's Functional Lateralization

    ERIC Educational Resources Information Center

    Mercure, Evelyne; Ashwin, Emma; Dick, Frederic; Halit, Hanife; Auyeung, Bonnie; Baron-Cohen, Simon; Johnson, Mark H.

    2009-01-01

    Previous event-related potential (ERP) studies have revealed that faces and words show a robust difference in the lateralization of their N170. The present study investigated the development of this differential lateralization in school-age boys. We assessed the potential role of fetal testosterone (FT) level as a factor biasing the prenatal…

  11. Fate of estradiol and testosterone in anaerobic lagoon digestors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laboratory-scale lagoon digestors were constructed, and the fate of 14C-labelled 17ß-estradiol (E2) and testosterone (Test) were monitored for 42 d anaerobically under biological and sterile conditions. Hormone levels decreased in the liquid layer and increased in the sludge with time. At 42 d, 16-2...

  12. Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a double-blind randomised clinical study.

    PubMed

    Rao, Amanda; Steels, Elizabeth; Inder, Warrick J; Abraham, Suzanne; Vitetta, Luis

    2016-06-01

    This study examined the effect of Testofen, a specialised Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function and serum androgen concentrations in healthy aging males. This was a double-blind, randomised, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardised Trigonella foenum-graecum seed extract at a dose of 600 mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in AMS score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment. Trigonella foenum-graecum seed extract is a safe and effective treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.

  13. Musculoskeletal and prostate effects of combined testosterone and finasteride administration in older hypogonadal men: a randomized, controlled trial.

    PubMed

    Borst, Stephen E; Yarrow, Joshua F; Conover, Christine F; Nseyo, Unyime; Meuleman, John R; Lipinska, Judyta A; Braith, Randy W; Beck, Darren T; Martin, Jeffrey S; Morrow, Matthew; Roessner, Shirley; Beggs, Luke A; McCoy, Sean C; Cannady, Darryl F; Shuster, Jonathan J

    2014-02-15

    Testosterone acts directly at androgen receptors and also exerts potent actions following 5α-reduction to dihydrotestosterone (DHT). Finasteride (type II 5α-reductase inhibitor) lowers DHT and is used to treat benign prostatic hyperplasia. However, it is unknown whether elevated DHT mediates either beneficial musculoskeletal effects or prostate enlargement resulting from higher-than-replacement doses of testosterone. Our purpose was to determine whether administration of testosterone plus finasteride to older hypogonadal men could produce musculoskeletal benefits without prostate enlargement. Sixty men aged ≥60 yr with a serum testosterone concentration of ≤300 ng/dl or bioavailable testosterone ≤70 ng/dl received 52 wk of treatment with testosterone enanthate (TE; 125 mg/wk) vs. vehicle, paired with finasteride (5 mg/day) vs. placebo using a 2 × 2 factorial design. Over the course of 12 mo, TE increased upper and lower body muscle strength by 8-14% (P = 0.015 to <0.001), fat-free mass 4.04 kg (P = 0.032), lumbar spine bone mineral density (BMD) 4.19% (P < 0.001), and total hip BMD 1.96% (P = 0.024) while reducing total body fat -3.87 kg (P < 0.001) and trunk fat -1.88 kg (P = 0.0051). In the first 3 mo, testosterone increased hematocrit 4.13% (P < 0.001). Coadministration of finasteride did not alter any of these effects. Over 12 mo, testosterone also increased prostate volume 11.4 cm(3) (P = 0.0051), an effect that was completely prevented by finasteride (P = 0.0027). We conclude that a higher-than-replacement TE combined with finasteride significantly increases muscle strength and BMD and reduces body fat without causing prostate enlargement. These results demonstrate that elevated DHT mediates testosterone-induced prostate enlargement but is not required for benefits in musculoskeletal or adipose tissue.

  14. Testosterone is associated with cooperation during intergroup competition by enhancing parochial altruism

    PubMed Central

    Reimers, Luise; Diekhof, Esther K.

    2015-01-01

    The steroid hormone testosterone is widely associated with negative behavioral effects, such as aggression or dominance. However, recent studies applying economic exchange tasks revealed conflicting results. While some point to a prosocial effect of testosterone by increasing altruistic behavior, others report that testosterone promotes antisocial tendencies. Taking into account additional factors such as parochial altruism (i.e., ingroup favoritism and outgroup hostility) might help to explain this contradiction. First evidence for a link between testosterone and parochial altruism comes from recently reported data of male soccer fans playing the ultimatum game. In this study high levels of endogenous testosterone predicted increased altruistic punishment during outgroup interactions and at the same time heightened ingroup generosity. Here, we report findings of another experimental task, the prisoner's dilemma, applied in the same context to examine the role of testosterone on parochial tendencies in terms of cooperation. In this task, 50 male soccer fans were asked to decide whether or not they wanted to cooperate with partners marked as either fans of the subject's own favorite team (ingroup) or fans of other teams (outgroups). Our results show that high testosterone levels were associated with increased ingroup cooperation during intergroup competition. In addition, subjects displaying a high degree of parochialism during intergroup competition had significantly higher levels of testosterone than subjects who did not differentiate much between the different groups. In sum, the present data demonstrate that the behavioral effects of testosterone are not limited to aggressive and selfish tendencies but may imply prosocial aspects depending on the context. By this means, our results support the previously reported findings on testosterone-dependent intergroup bias and indicate that this social hormone might be an important factor driving parochial altruism. PMID

  15. Testosterone Induces Erythrocytosis via Increased Erythropoietin and Suppressed Hepcidin: Evidence for a New Erythropoietin/Hemoglobin Set Point

    PubMed Central

    Travison, Thomas G.; Basaria, Shehzad; Davda, Maithili N.; Guo, Wen; Li, Michelle; Connor Westfall, John; Bae, Harold; Gordeuk, Victor; Bhasin, Shalender

    2014-01-01

    Background. The mechanisms by which testosterone increases hemoglobin and hematocrit remain unclear. Methods. We assessed the hormonal and hematologic responses to testosterone administration in a clinical trial in which older men with mobility limitation were randomized to either placebo or testosterone gel daily for 6 months. Results. The 7%–10% increase in hemoglobin and hematocrit, respectively, with testosterone administration was associated with significantly increased erythropoietin (EPO) levels and decreased ferritin and hepcidin levels at 1 and 3 months. At 6 months, EPO and hepcidin levels returned toward baseline in spite of continued testosterone administration, but EPO levels remained nonsuppressed even though elevated hemoglobin and hematocrit higher than at baseline, suggesting a new set point. Consistent with increased iron utilization, soluble transferrin receptor (sTR) levels and ratio of sTR/log ferritin increased significantly in testosterone-treated men. Hormonal and hematologic responses were similar in anemic participants. The majority of testosterone-treated anemic participants increased their hemoglobin into normal range. Conclusions. Testosterone-induced increase in hemoglobin and hematocrit is associated with stimulation of EPO and reduced ferritin and hepcidin concentrations. We propose that testosterone stimulates erythropoiesis by stimulating EPO and recalibrating the set point of EPO in relation to hemoglobin and by increasing iron utilization for erythropoiesis. PMID:24158761

  16. Hot or Not: The Effects of Exogenous Testosterone on Female Attractiveness to Male Conspecifics in the Budgerigar

    PubMed Central

    Lahaye, Stefanie E. P.; Eens, Marcel; Darras, Veerle M.; Pinxten, Rianne

    2013-01-01

    An increasing number of studies indicate that not only females but also males can be selective when choosing a mate. In species exhibiting male or mutual mate choice, females may benefit from being attractive. While male attractiveness is often positively influenced by higher plasma levels of the androgenic hormone testosterone, it has been shown that testosterone can masculinise female behavior and morphology in several bird species, potentially rendering them less attractive. In this study, we investigated whether female budgerigars, Melopsittacusundulatus, suffer from increased plasma testosterone levels through a negative effect on their attractiveness to males. We experimentally increased plasma testosterone levels in testosterone-treated females (T-females) compared to controls (C-females) and allowed males to choose between a T- and a C-female in a two-way choice situation. Although testosterone treatment significantly affected female behavioral and morphological characteristics, males did not show a significant difference in preference between T- and C-females. These results suggest that experimentally increasing testosterone levels in females does not appear to influence male preference during initial mate choice. Our findings indicate that selection for higher levels of testosterone in male budgerigars is probably not constrained by a correlated response to selection causing negative effects on female attractiveness during initial mate choice. Evaluating whether or not a potential constraint may arise from negative testosterone-induced effects on other fitness related traits in females requires further work. PMID:23951365

  17. Testosterone-to-oestradiol ratio is associated with female facial attractiveness.

    PubMed

    Probst, Fabian; Bobst, Cora; Lobmaier, Janek S

    2016-01-01

    The relationship between facial shape and attractiveness has been extensively studied, yet few studies have investigated the underlying biological factors of an attractive face. Many researchers have proposed a link between female attractiveness and sex hormones, but there is little empirical evidence in support of this assumption. In the present study we investigated the relationship between circulating sex hormones and attractiveness. We created prototypes by separately averaging photographs of 15 women with high and low levels of testosterone, oestradiol, and testosterone-to-oestradiol ratio levels, respectively. An independent set of facial images was then shape transformed toward these prototypes. We paired the resulting images in such a way that one face depicted a female with high hormone level and the other one with a low hormone level. Fifty participants were asked to choose the more attractive face of each pair. We found that low testosterone-to-oestradiol ratio and low testosterone were positively associated with female facial attractiveness. There was no preference for faces with high oestradiol levels. In an additional experiment with 36 participants we confirmed that a low testosterone-to-oestradiol ratio plays a larger role than low testosterone alone. These results provide empirical evidence that an attractive female face is shaped by interacting effects of testosterone and oestradiol.

  18. Parents’ Testosterone and Children’s Perception of Parent-Child Relationship Quality

    PubMed Central

    Booth, Alan; Hibel, Jacob; Granger, Douglas A.; Johnson, David

    2011-01-01

    We examine the link between parental testosterone and children’s perceptions of their relationship with their mother and father. Using data from 352 predominantly white working and middle class families, we find no direct link between mother’s and father’s testosterone and parent-child closeness. However, the association between mothers’ testosterone and mother-child closeness appears to be influenced by the quality of two other family relationships. When father’s marital satisfaction is low, mothers with high testosterone have a poorer relationship with their children. And, when fathers report low levels of intimacy with their children, high testosterone women have a poorer relationship with their children. No comparable associations were observed among fathers. PMID:21843525

  19. Status, testosterone, and human intellectual performance: stereotype threat as status concern.

    PubMed

    Josephs, Robert A; Newman, Mathew L; Brown, Ryan P; Beer, Jeremy M

    2003-03-01

    Results from two experiments suggest that stereotype-threat effects are special cases of a more general process involving the need to maintain or enhance status. We hypothesized that situations capable of confirming a performance stereotype might represent either a threat to status or an opportunity for enhancement of status, depending on the nature of the stereotype. The positive relationship between baseline testosterone and status sensitivity led us to hypothesize that high testosterone levels in males and females would amplify existing performance expectations when gender-based math-performance stereotypes were activated. In Study 1, high-testosterone females performed poorly on a math test when a negative performance stereotype was primed. In Study 2, high-testosterone males excelled on a math test when a positive performance stereotype was primed. The moderating effect of testosterone on performance suggests that a stereotype-relevant situation is capable of conferring either a loss or a gain of status on targets of the stereotype.

  20. Testosterone replacement effectively inhibits the development of experimental autoimmune orchitis in rats: evidence for a direct role of testosterone on regulatory T cell expansion.

    PubMed

    Fijak, Monika; Schneider, Eva; Klug, Jörg; Bhushan, Sudhanshu; Hackstein, Holger; Schuler, Gerhard; Wygrecka, Malgorzata; Gromoll, Jörg; Meinhardt, Andreas

    2011-05-01

    Despite the immune-privileged status of the male genital tract, infection and inflammation of the male genital tract are important etiological factors in male infertility. A common observation in clinical and experimental orchitis as well as in systemic infection and inflammation are decreased levels of testosterone. Emerging data point to an immunosuppressive role of testosterone. In our study, we substituted testosterone levels in experimental autoimmune orchitis (EAO) in rat by s.c. testosterone implants. EAO development was reduced to 17% when animals were treated with low-dose testosterone implants (3 cm long, EAO+T3) and to 33% when rats were supplied with high-dose testosterone implants (24 cm, EAO+T24) compared with 80% of animals developing disease in the EAO control group. In the testis, testosterone replacement in EAO animals prevented the accumulation of macrophages and significantly reduced the number of CD4(+) T cells with a strong concomitant increase in the number of regulatory T cells (CD4(+)CD25(+)Foxp3(+)) compared with EAO control. In vitro testosterone treatment of naive T cells led to an expansion of the regulatory T cell subset with suppressive activity and ameliorated MCP-1-stimulated chemotaxis of T lymphocytes in a Transwell assay. Moreover, expression of proinflammatory mediators such as MCP-1, TNF-α, and IL-6 in the testis and secretion of Th1 cytokines such as IFN-γ and IL-2 by mononuclear cells isolated from testicular draining lymph nodes were decreased in the EAO+T3 and EAO+T24 groups. Thus, our study shows an immunomodulatory and protective effect of testosterone substitution in the pathogenesis of EAO and suggests androgens as a new factor in the differentiation of regulatory T cells.

  1. Taenia taeniaeformis: inhibition of rat testosterone production by excretory-secretory product of the cultured metacestode.

    PubMed

    Rikihisa, Y; Lin, Y C; Fukaya, T

    1985-06-01

    In 3- to 5-month-old male Sprague-Dawley rats infected with the hepatic metacestode, Taenia taeniaeformis, the serum testosterone level was significantly lower than in comparable uninfected controls. By transmission electron microscopy, testicular Leydig cells of infected rats had less smooth endoplasmic reticulum than control Leydig cells. Cultured metacestodes isolated from the hepatic cysts secreted or excreted substances into the incubation medium. The effect of the excretory-secretory product on testosterone concentration in the sera and testes of 15-day-old rats was examined. Subcutaneous injection of 50-200 micrograms of excretory-secretory product/0.1 ml saline/rat for 2 days significantly reduced human chorionic gonadotropin-stimulated serum and testicular testosterone concentrations. Furthermore, the effect of the excretory-secretory product on isolated rat Leydig cell testosterone production was examined. Rat Leydig cells produced testosterone in vitro and, in the presence of 50 IU human chorionic gonadotropin/ml incubation medium, they responded with approximately 100% increase in testosterone production. Addition of 2-10 micrograms excretory-secretory product protein/ml of culture medium significantly reduced the testosterone production by rat Leydig cells in vitro. These results indicate that excretory-secretory product of cultured T. taeniaeformis metacestodes has a direct inhibitory effect on Leydig cell testosterone production under stimulation with human chorionic gonadotropin.

  2. Effects of testosterone and 5alpha-dihydrotestosterone on luteal lifespan in dairy heifers.

    PubMed

    Silvia, W J; Jacobs, A L; Hayes, S H

    1989-11-01

    Endogenous concentrations of testosterone increase approximately 7 d prior to estrus in cattle and goats. Inhibition of testosterone synthesis results in a delay of luteal regression in both species. The purpose of this experiment was to determine if treatment with testosterone or 5alpha-dihydrotestosterone (DHT), 2 to 6 d prior to the endogenous rise in testosterone, would result in premature luteal regression. Sixteen heifers were randomly assigned to one of three treatment groups: 1) Control (n = 6); 2) testosterone (100 mug, n = 5); or 3) DHT (100 mug, n = 5). Each heifer received a single injection of the appropriate steriod on Day 8, 9, 10, 11 or 12 post estrus. Jugular venous blood samples were collected at frequent intervals for 24 h to quantify testosterone, and then daily for 14 d to quantify progesterone. Concentrations of testosterone increased within 15 min of injection of testosterone, and reached a maximum at 30 min. Concentrations were maintained at > 2 ng/ml throughout the first 24 h after injection. Based on concentrations of progesterone, neither androgen had any effect on the lifespan of the corpus luteum or the level of luteal function.

  3. Effects of Testosterone Therapy on Cognitive Function in Aging: A Systematic Review.

    PubMed

    Hua, Jeremy T; Hildreth, Kerry L; Pelak, Victoria S

    2016-09-01

    Endogenous testosterone in the aging man has been scrutinized extensively in regard to its effects on performance in many cognitive domains, especially verbal fluency, visuospatial and visuoperceptual abilities, memory, and executive function. Studies of testosterone supplementation have sought to identify potential cognitive improvements in men with and without baseline cognitive impairment, and have had a wide range of results. The variability in outcomes is likely related, in part, to the lack of consensus on methods for testosterone measurement and supplementation and, in part, to the disparate measures of cognitive function used in randomized controlled studies. Despite the limitations imposed by such inconsistent methods, promising associations have been found between cognition and testosterone supplementation in both eugonadal men and men with low testosterone levels, with and without baseline cognitive dysfunction. This systematic review highlights the cognitive measures used in and the outcomes of existing studies of testosterone and cognition in aging men. The review suggests that larger studies and a more standardized approach to assessment will be needed before we can fully understand and realize sustained benefits from testosterone supplementation in the elderly male population, particularly given the substantial increase in testosterone supplementation in clinical practice.

  4. Aggressive behavior and change in salivary testosterone concentrations predict willingness to engage in a competitive task.

    PubMed

    Carré, Justin M; McCormick, Cheryl M

    2008-08-01

    The current study investigated relationships among aggressive behavior, change in salivary testosterone concentrations, and willingness to engage in a competitive task. Thirty-eight male participants provided saliva samples before and after performing the Point Subtraction Aggression Paradigm (a laboratory measure that provides opportunity for aggressive and defensive behavior while working for reward; all three involve pressing specific response keys). Baseline testosterone concentrations were not associated with aggressive responding. However, aggressive responding (but not point reward or point protection responding) predicted the pre- to post-PSAP change in testosterone: Those with the highest aggressive responding had the largest percent increase in testosterone concentrations. Together, aggressive responding and change in testosterone predicted willingness to compete following the PSAP. Controlling for aggression, men who showed a rise in testosterone were more likely to choose to compete again (p=0.03) and controlling for testosterone change, men who showed the highest level of aggressive responding were more likely to choose the non-competitive task (p=0.02). These results indicate that situation-specific aggressive behavior and testosterone responsiveness are functionally relevant predictors of future social behavior.

  5. Detection of testosterone esters in blood.

    PubMed

    Forsdahl, Guro; Erceg, Damir; Geisendorfer, Thomas; Turkalj, Mirjana; Plavec, Davor; Thevis, Mario; Tretzel, Laura; Gmeiner, Günter

    2015-01-01

    Injections of synthetic esters of testosterone are among the most common forms of testosterone application. In doping control, the detection of an intact ester of testosterone in blood gives unequivocal proof of the administration of exogenous testosterone. The aim of the current project was to investigate the detection window for injected testosterone esters as a mixed substance preparation and as a single substance preparation in serum and plasma. Furthermore, the suitability of different types of blood collection devices was evaluated. Collection tubes with stabilizing additives, as well as non-stabilized serum separation tubes, were tested. A clinical study with six participants was carried out, comprising a single intramuscular injection of either 1000 mg testosterone undecanoate (Nebido(®)) or a mixture of 30 mg testosterone propionate, 60 mg testosterone phenylpropionate, 60 mg testosterone isocaproate, and 100 mg testosterone decanoate (Sustanon(®)). Blood was collected throughout a testing period of 60 days. The applied analytical method for blood analysis included liquid-liquid extraction and preparation of oxime derivatives, prior to TLX-sample clean-up and liquid chromatography-tandem mass spectrometry (LC-MS/MS) detection. All investigated testosterone esters could be detected in post-administration blood samples. The detection time depended on the type of ester administered. Furthermore, results from the study show that measured blood concentrations of especially short-chained testosterone esters are influenced by the type of blood collection device applied. The testosterone ester detection window, however, was comparable.

  6. Testosterone therapy and prostate cancer

    PubMed Central

    Pastuszak, Alexander W.; Rodriguez, Katherine M.; Nguyen, Taylor M.

    2016-01-01

    The use of exogenous testosterone to treat hypogonadism in the men with a history of prostate cancer (CaP) remains controversial due to fears of cancer recurrence or progression. Due to the detrimental impact of hypogonadism on patient quality of life, recent work has examined the safety of testosterone therapy (TTh) in men with a history of CaP. In this review, we evaluate the literature with regards to the safety of TTh in men with a history of CaP. TTh results in improvements in quality of life with little evidence of biochemical recurrence or progression in men with a history of CaP, or de novo cancer in unaffected men. An insufficient amount of evidence is currently available to truly demonstrate the safe use of TTh in men with low risk CaP. In men with high-risk cancer, more limited data suggest that TTh may be safe, but these findings remain inconclusive. Despite the historic avoidance of TTh in men with a history of CaP, the existing body of evidence largely supports the safe and effective use of testosterone in these men, although additional study is needed before unequivocal safety can be demonstrated. PMID:28078223

  7. The hidden dimensions of the competition effect: basal cortisol and basal testosterone jointly predict changes in salivary testosterone after social victory in men.

    PubMed

    Zilioli, Samuele; Watson, Neil V

    2012-11-01

    Dominance struggles appear to affect hormone concentrations in many mammalian species, such that higher concentrations of testosterone are seen in winners of competitions, compared to losers. This so-called, "competition effect" has received inconsistent empirical support, suggesting that additional psychological (e.g., mood), situational (i.e., nature of the competition) and physiological (e.g., cortisol) variables might intervene in modulating testosterone fluctuations after social contests. We investigated possible interactions between the hypothalamic-pituitary-gonadal (HPG) axis and the hypothalamic-pituitary-adrenal (HPA) stress axis in predicting transient changes in testosterone after social victory or defeat on a familiar competitive task. In particular, the present study examined the dual-hormone hypothesis - proposing that baseline cortisol potently modulates the competition effect (Mehta and Josephs, 2010) - in a sample of healthy young men engaged in head-to-head competition on a widely played commercial videogame, Tetris. We found a significant interaction between HPG and HPA axes status and the competition effect on testosterone in the randomly assigned videogame winners, such that winners with a pre-competition combination of high baseline testosterone and low baseline cortisol exhibited significantly greater post-competition testosterone concentrations. The randomly assigned videogame losers showed significantly decreased post-competition levels of testosterone. Possible biological and evolutionary mechanisms underlying this phenomenon are discussed.

  8. Determination of Zinc, Cadmium and Lead Bioavailability in Contaminated Soils at the Single-Cell Level by a Combination of Whole-Cell Biosensors and Flow Cytometry

    PubMed Central

    Hurdebise, Quentin; Tarayre, Cédric; Fischer, Christophe; Colinet, Gilles; Hiligsmann, Serge; Delvigne, Frank

    2015-01-01

    Zinc, lead and cadmium are metallic trace elements (MTEs) that are widespread in the environment and tend to accumulate in soils because of their low mobility and non-degradability. The purpose of this work is to evaluate the applicability of biosensors as tools able to provide data about the bioavailability of such MTEs in contaminated soils. Here, we tested the genetically-engineered strain Escherichia coli pPZntAgfp as a biosensor applicable to the detection of zinc, lead and cadmium by the biosynthesis of green fluorescent protein (GFP) accumulating inside the cells. Flow cytometry was used to investigate the fluorescence induced by the MTEs. A curvilinear response to zinc between 0 and 25 mg/L and another curvilinear response to cadmium between 0 and 1.5 mg/L were highlighted in liquid media, while lead did not produce exploitable results. The response relating to a Zn2+/Cd2+ ratio of 10 was further investigated. In these conditions, E. coli pPZntAgfp responded to cadmium only. Several contaminated soils with a Zn2+/Cd2+ ratio of 10 were analyzed with the biosensor, and the metallic concentrations were also measured by atomic absorption spectroscopy. Our results showed that E. coli pPZntAgfp could be used as a monitoring tool for contaminated soils being processed. PMID:25894939

  9. A clinical update on female androgen insufficiency--testosterone testing and treatment in women presenting with low sexual desire.

    PubMed

    Burger, Henry G; Papalia, Mary-Anne

    2006-05-01

    The diagnosis of female androgen deficiency syndrome is suggested by complaints of a diminished sense of well being, persistent unexplained fatigue and decreased sexual desire, sexual receptivity and pleasure in a woman who is oestrogen-replete and in whom no other significant contributing factors can be identified. The diagnosis is supported by the finding of low circulating concentrations of free testosterone. Barriers to its recognition include the non-specificity of the symptoms and methodological problems due to insensitive testosterone assays. Barriers to its treatment include the unavailability of satisfactory forms of testosterone for administration to women and lack of data regarding long-term safety. Although several conditions lead to clear-cut androgen deficiency, such as hypopituitarism, adrenal and ovarian insufficiency, glucocorticoid therapy and use of oral contraceptives and oral oestrogens, it is important for clinicians to recognise that in normal women, androgen levels decline by 50% from the early 20s to the mid 40s, and hence age-related androgen insufficiency may occur in women in their late 30s and 40s, as well as postmenopausally. Satisfactory measurements of free testosterone requires a sensitive and reliable assay for total testosterone, and quantitation of sex hormone binding globulin, from which free testosterone is readily calculated. Adverse effects of testosterone treatment are few if replacement is monitored to achieve physiological circulating testosterone concentrations. Currently, available methods include testosterone implants and testosterone creams, and transdermal patches and sprays are in development.

  10. Zinc bioavailability in pork loin

    SciTech Connect

    Hortin, A.E.; Bechtel, P.J. Baker, D.H. )

    1991-03-15

    Pork loins were uniformly trimmed and divided into three groups: raw, roasted and braised. Following cooking, the loins were freeze dried and then ground to a fine granular consistency. Zinc levels of 51, 60 and 63 mg/kg dry matter (DM) were contained in the raw, roasted and braised products, respectively. The chick bioavailability (BV) assay employed a Zn-deficient soy isolate basal diet that was supplemented with 0, 5 or 10 mg Zn/kg from ZnSO{sub 4}{center dot}H{sub 2}O to produce a standard straight-line response in tibia Zn as a function of supplemental Zn intake. Experimental Zn sources were also added to the basal diet to provide 10 mg Zn/kg. Standard curve methodology indicated that Zn BV was unaffected by cooking. Roasted pork lion had a Zn BV of 184% relative to ZnSO{sub 4}{center dot}H{sub 2}O. Addition of 0.40% L-cysteine to the diet containing 10 mg Zn/kg from ZnSO{sub 4}{center dot}H{sub 2}O increased Zn BV to 175%. Results with histidine as a Zn-enhancing factor were variable. It is apparent that pork loin is an excellent source of bioavailable Zn, and SH-containing compounds such as cysteine and glutathione that are present in meat may contribute to enhanced gut absorption of meat-source Zn.

  11. Plasma cortisol and testosterone following 19-km and 42-km kayak races.

    PubMed

    Lutoslawska, G; Obminski, Z; Krogulski, A; Sendecki, W

    1991-12-01

    Plasma cortisol and testosterone levels were examined in five, elite, male kayakers before and after 19-km and 42-km kayak races. Both races resulted in significant elevation in plasma cortisol and observed increase is likely to depend on race duration, being much more pronounced after 42-km race compared to 19-km. It should be stressed that observed elevation in cortisol level after 42-km race was higher than reported previously after a marathon run. This finding is in line with reports on hormonal changes in response to arms exercise. Both contests caused a decrease in plasma testosterone level, but the difference between races was not significant. Testosterone/cortisol ratio dropped significantly immediately after the races and the observed decrease was more dominant after the 42-km distance. On the next day, 18 h after the races plasma cortisol, testosterone levels and T/C ratio returned to basal level indicating recuperation from post exercise changes.

  12. In vitro and in vivo evaluation of a novel testosterone transdermal delivery system (TTDS) using palm oil base

    PubMed Central

    Haron, Didi Erwandi Mohamad; Chik, Zamri; Noordin, Mohamed Ibrahm; Mohamed, Zahurin

    2015-01-01

    Objective (s): Transdermal preparations for testosterone are becoming popular because of their unique advantages such as avoidance of first-pass effect, convenience, improved bioavailability, and reduction of systemic side effects. A novel testosterone transdermal delivery system (TDDS) was developed using a palm oil base called HAMIN™ (a commercial product) and tested using in vitro and in vivo skin permeability test methods. Materials and Methods: The physical characteristics of the formulation such as particle size and viscosity were determined by using Franz diffusion cell and Brookfield viscometer, respectively. In vivo skin permeability test was performed on healthy rabbits through the skin. Testosterone in serum was analyzed using the validated Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) technique. Results: In vitro study showed that the cumulative amount of testosterone diffused was between 40 to 1400 ngcm-² over a period of five hr after application of TDDS through the artificial Strat-M™ membrane. In the in vivo rabbit skin permeability test, the results indicated that testosterone was well absorbed with a mean Cmax and Tmax of 60.94 ngml-1 and 2.29 hr after application of TDDS while no increase was observed in placebo treatment. Particle size analysis ranged from 79.4 nm to 630.0 nm for placebo and 97 to 774.0 nm for TDDS. Conclusion: The formulation was successfully prepared using HAMIN™, which has demonstrated great potential for topical delivery of testosterone. PMID:26877845

  13. A quantitative and qualitative review of the effects of testosterone on the function and structure of the human social-emotional brain.

    PubMed

    Heany, Sarah J; van Honk, Jack; Stein, Dan J; Brooks, Samantha J

    2016-02-01

    Social and affective research in humans is increasingly using functional and structural neuroimaging techniques to aid the understanding of how hormones, such as testosterone, modulate a wide range of psychological processes. We conducted a meta-analysis of functional magnetic resonance imaging (fMRI) studies of testosterone administration, and of fMRI studies that measured endogenous levels of the hormone, in relation to social and affective stimuli. Furthermore, we conducted a review of structural MRI i.e. voxel based morphometry (VBM) studies which considered brain volume in relation to testosterone levels in adults and in children. In the included testosterone administration fMRI studies, which consisted of female samples only, bilateral amygdala/parahippocampal regions as well as the right caudate were significantly activated by social-affective stimuli in the testosterone condition. In the studies considering endogenous levels of testosterone, stimuli-invoked activations relating to testosterone levels were noted in the bilateral amygdala/parahippocampal regions and the brainstem. When the endogenous testosterone studies were split by sex, the significant activation of the brain stem was seen in the female samples only. Significant stimuli-invoked deactivations relating to endogenous testosterone levels were also seen in the right and left amygdala/parahippocampal regions studies. The findings of the VBM studies were less consistent. In adults larger volumes in the limbic and temporal regions were associated with higher endogenous testosterone. In children, boys showed a positive correlation between testosterone and brain volume in many regions, including the amygdala, as well as global grey matter volume, while girls showed a neutral or negative association between testosterone levels and many brain volumes. In conclusion, amygdalar and parahippocampal regions appear to be key target regions for the acute actions of testosterone in response to social and

  14. Are rapid changes in gonadal testosterone release involved in the fast modulation of brain estrogen effects?

    PubMed Central

    Cornil, Charlotte A.; Stevenson, Tyler J.; Ball, Gregory F.

    2009-01-01

    Estradiol facilitates the expression of male sexual behavior in Japanese quail within a few minutes. These rapid behavioral effects of estradiol could result from rapid changes in its local production in the preoptic area by aromatase, the enzyme converting testosterone into estradiol. Alternatively, aromatase activity may remain constant but fluctuations of local estradiol production could arise from rapid changes in the concentration of the enzymatic substrate, namely testosterone. Rapid increases of circulating testosterone levels have been observed in males of various species following social encounters. Surprisingly, in quail, the interaction with a female seems to result in a decrease in circulating testosterone levels. However, in that study conducted in quail, the samples were collected at intervals longer than the recently observed rapid effects of estradiol on sexual behavior. In the present study we investigated whether plasma testosterone concentrations fluctuate on a shorter time-frame. Eleven male were tested 5 min before and 5, 15 or 30 min after being allowed to have visual access to a female or to copulate with a female for 5 min. Both types of interactions resulted in a significant decline in circulating testosterone levels at latencies as short as 5 min. These data demonstrate that the decrease in testosterone levels is initiated shortly after sexual encounters. Because visual interactions with a female did not result in a rapid increase in testosterone concentrations, these findings rule out the possibility that a rapid rise in circulating testosterone levels participates in the rapid increase in brain estrogen synthesis and its facilitatory effects on copulatory behavior. PMID:19416729

  15. [Hemoglobin and testosterone: importance on high altitude acclimatization and adaptation].

    PubMed

    Gonzales, Gustavo F

    2011-03-01

    The different types of response mechanisms that the organism uses when exposed to hypoxia include accommodation, acclimatization and adaptation. Accommodation is the initial response to acute exposure to high altitude hypoxia and is characterized by an increase in ventilation and heart rate. Acclimatization is observed in individuals temporarily exposed to high altitude, and to some extent, it enables them to tolerate the high altitudes. In this phase, erythropoiesis is increased, resulting in higher hemoglobin and hematocrit levels to improve oxygen delivery capacity. Adaptation is the process of natural acclimatization where genetical variations and acclimatization play a role in allowing subjects to live without any difficulties at high altitudes. Testosterone is a hormone that regulates erythropoiesis and ventilation and could be associated to the processes of acclimatization and adaptation to high altitude. Excessive erythrocytosis, which leads to chronic mountain sickness, is caused by low arterial oxygen saturation, ventilatory inefficiency and reduced ventilatory response to hypoxia. Testosterone increases during acute exposure to high altitude and also in natives at high altitude with excessive erythrocytosis. Results of current research allow us to conclude that increase in serum testosterone and hemoglobin is adequate for acclimatization, as they improve oxygen transport, but not for high altitude adaptation, since high serum testosterone levels are associated to excessive erythrocytosis.

  16. Effects of Nandrolone Stimulation on Testosterone Biosynthesis in Leydig Cells

    PubMed Central

    Barone, Rosario; Marino Gammazza, Antonella; Sangiorgi, Claudia; Barone, Fulvio; Pitruzzella, Alessandro; Locorotondo, Nicola; Di Gaudio, Francesca; Salerno, Monica; Maglietta, Francesca; Sarni, Antonio Luciano; Di Felice, Valentina; Cappello, Francesco; Turillazzi, Emanuela

    2015-01-01

    Anabolic androgenic steroids (AAS) are among the drugs most used by athletes for improving physical performance, as well as for aesthetic purposes. A number of papers have showed the side effects of AAS in different organs and tissues. For example, AAS are known to suppress gonadotropin‐releasing hormone, luteinizing hormone, and follicle‐stimulating hormone. This study investigates the effects of nandrolone on testosterone biosynthesis in Leydig cells using various methods, including mass spectrometry, western blotting, confocal microscopy and quantitative real‐time PCR. The results obtained show that testosterone levels increase at a 3.9 μM concentration of nandrolone and return to the basal level a 15.6 μM dose of nandrolone. Nandrolone‐induced testosterone increment was associated with upregulation of the steroidogenic acute regulatory protein (StAR) and downregulation of 17a‐hydroxylase/17, 20 lyase (CYP17A1). Instead, a 15.6 µM dose of nandrolone induced a down‐regulation of CYP17A1. Further in vivo studies based on these data are needed to better understand the relationship between disturbed testosterone homeostasis and reproductive system impairment in male subjects. J. Cell. Physiol. 231: 1385–1391, 2016. © 2015 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc. PMID:26626779

  17. Impact of Testosterone Replacement Therapy on Myocardial Infarction, Stroke, and Death in Men With Low Testosterone Concentrations in an Integrated Health Care System.

    PubMed

    Anderson, Jeffrey L; May, Heidi T; Lappé, Donald L; Bair, Tami; Le, Viet; Carlquist, John F; Muhlestein, Joseph B

    2016-03-01

    The aim of this study was to assess the effect of testosterone replacement therapy (TRT) on cardiovascular outcomes. Men (January 1, 1996, to December 31, 2011) with a low initial total testosterone concentration, a subsequent testosterone level, and >3 years of follow-up were studied. Levels were correlated with testosterone supplement use. The primary outcome was major adverse cardiovascular events (MACE), defined as a composite of death, nonfatal myocardial infarction, and stroke at 3 years. Multivariate adjusted hazard ratios (HRs) comparing groups of persistent low (<212 ng/dl, n = 801), normal (212 to 742 ng/dl, n = 2,241), and high (>742 ng/dl, n = 1,694) achieved testosterone were calculated by Cox hazard regression. A total of 4,736 men were studied. Three-year rates of MACE and death were 6.6% and 4.3%, respectively. Subjects supplemented to normal testosterone had reduced 3-year MACE (HR 0.74; 95% confidence interval [CI] 0.56 to 0.98, p = 0.04) compared to persistently low testosterone, driven primarily by death (HR 0.65, 95% CI 0.47 to 0.90). HRs for MI and stroke were 0.73 (95% CI 0.40 to 1.34), p = 0.32, and 1.11 (95% CI 0.54 to 2.28), p = 0.78, respectively. MACE was noninferior but not superior for high achieved testosterone with no benefit on MI and a trend to greater stroke risk. In conclusion, in a large general health care population, TRT to normal levels was associated with reduced MACE and death over 3 years but a stroke signal with high achieved levels suggests a conservative approach to TRT.

  18. Environmental exposure to metals and male reproductive hormones: Circulating testosterone is inversely associated with blood molybdenum

    PubMed Central

    Meeker, John D.; Rossano, Mary G.; Protas, Bridget; Padmanabhan, Vasantha; Diamond, Michael P.; Puscheck, Elizabeth; Daly, Douglas; Paneth, Nigel; Wirth, Julia J.

    2010-01-01

    Study Objective To explore associations between exposure to metals and male reproductive hormone levels. Design Cross-sectional epidemiology study with adjustment for potential confounders. Setting Metal concentrations and reproductive hormone levels were measured in blood samples collected from 219 men. Patients: Men recruited through two Michigan, USA infertility clinics. Interventions None Main Outcome Measures Serum FSH, LH, inhibin B, testosterone, and SHBG. Results Cadmium, copper and lead were all significantly or suggestively positively associated with testosterone when modeled individually (p-values = 0.1, 0.03, and 0.07, respectively), findings that are consistent with limited previous human and animal studies. Conversely, molybdenum was associated with reduced testosterone (p-value for trend = 0.001). A significant inverse trend between molybdenum and testosterone remained when additionally considering other metals in the model, where a positive association between testosterone and zinc was also found. Finally, in exploratory analysis there was evidence for an interaction between molybdenum and zinc, where high molybdenum was associated with a 37% reduction in testosterone (relative to the population median level) among men with low zinc. Conclusions While reductions in testosterone and reproductive toxicity following molybdenum exposure have been previously demonstrated in animal studies, more research is needed to determine whether molybdenum poses a risk to human reproductive health. PMID:18990371

  19. Treatment of pain in fibromyalgia patients with testosterone gel: Pharmacokinetics and clinical response.

    PubMed

    White, Hillary D; Brown, Lin A J; Gyurik, Robert J; Manganiello, Paul D; Robinson, Thomas D; Hallock, Linda S; Lewis, Lionel D; Yeo, Kiang-Teck J

    2015-08-01

    To test our hypothesis that testosterone deficiency plays an important role in chronic pain, a Phase I/II pilot study was initiated with 12 fibromyalgia patients to verify that a daily dose for 28days with transdermal testosterone gel would 1) significantly and safely increase mean serum testosterone concentrations from low baseline levels to mid/high-normal levels, and 2) effectively treat the pain and fatigue symptoms of fibromyalgia. Pharmacokinetic data confirmed that serum free testosterone concentrations were raised significantly above baseline levels, by assessment of maximum hormone concentration (Cmax) and area under the curve (AUC) parameters: free testosterone Cmax was significantly raised from a mean of 2.64pg/mL to 3.91pg/mL (p<0.05), and 24hour free testosterone AUC was significantly raised from a mean of 35.0pg-hr/mL to 53.89pg-hr/mL. Assessment of the typical symptoms of fibromyalgia by patient questionnaire and tender point exam demonstrated significant change in: decreased muscle pain, stiffness, and fatigue, and increased libido during study treatment. These results are consistent with the hypothesized ability of testosterone to relieve the symptoms of fibromyalgia. Symptoms not tightly related to fibromyalgia were not improved.

  20. The age-testosterone relationship in black, white, and Mexican-American men, and reasons for ethnic differences.

    PubMed

    Mazur, Allan

    2009-01-01

    Recent studies give contradictory findings regarding testosterone levels in white, black, and Hispanic men. Here, I present a cross-sectional reanalysis of serum testosterone and sex hormone-binding globulin (SHBG) in 1637 males, aged 12-90, who participated in the morning examination of the Third National Health and Nutrition Examination Survey (NHANES III) during the year 1988-1991. Testosterone and SHBG in males are described precisely over the age range 12 to 90 years. Testosterone and SHBG are not notably different in white and Mexican-American (MA) males. In the age range 20-69 years, black men average 0.39 ng/ml higher testosterone than white and MA men (p < 0.001). The higher testosterone in black men is partly explained by low marriage rate and low adiposity.

  1. Testosterone reduces AGTR1 expression to prevent β-cell and islet apoptosis from glucotoxicity.

    PubMed

    Kooptiwut, Suwattanee; Hanchang, Wanthanee; Semprasert, Namoiy; Junking, Mutita; Limjindaporn, Thawornchai; Yenchitsomanus, Pa-thai

    2015-03-01

    Hypogonadism in men is associated with an increased incidence of type 2 diabetes. Supplementation with testosterone has been shown to protect pancreatic β-cell against apoptosis due to toxic substances including streptozotocin and high glucose. One of the pathological mechanisms of glucose-induced pancreatic β-cell apoptosis is the induction of the local rennin-angiotensin-aldosterone system (RAAS). The role of testosterone in regulation of the pancreatic RAAS is still unknown. This study aims to investigate the protective action of testosterone against glucotoxicity-induced pancreatic β-cell apoptosis via alteration of the pancreatic RAAS pathway. Rat insulinoma cell line (INS-1) cells or isolated male mouse islets were cultured in basal and high-glucose media in the presence or absence of testosterone, losartan, and angiotensin II (Ang II), then cell apoptosis, cleaved caspase 3 expression, oxidative stress, and expression of angiotensin II type 1 receptor (AGTR1) and p47(phox) mRNA and protein were measured. Testosterone and losartan showed similar effects in reducing pancreatic β-cell apoptosis. Testosterone significantly reduced expression of AGTR1 protein in INS-1 cells cultured in high-glucose medium or high-glucose medium with Ang II. Testosterone decreased the expression of AGTR1 and p47(phox) mRNA and protein in comparison with levels in cells cultured in high-glucose medium alone. Furthermore, testosterone attenuated superoxide production when co-cultured with high-glucose medium. In contrast, when cultured in basal glucose, supplementation of testosterone did not have any effect on cell apoptosis, oxidative stress, and expression of AGT1R and p47(phox). In addition, high-glucose medium did not increase cleaved caspase 3 in AGTR1 knockdown experiments. Thus, our results indicated that testosterone prevents pancreatic β-cell apoptosis due to glucotoxicity through reduction of the expression of ATGR1 and its signaling pathway.

  2. Radiotherapy for Rectal Cancer Is Associated With Reduced Serum Testosterone and Increased FSH and LH

    SciTech Connect

    Bruheim, Kjersti Svartberg, Johan; Carlsen, Erik; Dueland, Svein; Haug, Egil; Skovlund, Eva; Tveit, Kjell Magne; Guren, Marianne G.

    2008-03-01

    Purpose: It is known that scattered radiation to the testes during pelvic radiotherapy can affect fertility, but there is little knowledge on its effects on male sex hormones. The aim of this study was to determine whether radiotherapy for rectal cancer affects testosterone production. Methods and Materials: All male patients who had received adjuvant radiotherapy for rectal cancer from 1993 to 2003 were identified from the Norwegian Rectal Cancer Registry. Patients treated with surgery alone were randomly selected from the same registry as control subjects. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and sex hormone binding globulin (SHBG) were analyzed, and free testosterone was calculated (N = 290). Information about the radiotherapy treatment was collected from the patient hospital charts. Results: Serum FSH was 3 times higher in the radiotherapy group than in the control group (median, 18.8 vs. 6.3 IU/L, p <0.001), and serum LH was 1.7 times higher (median, 7.5 vs. 4.5 IU/l, p <0.001). In the radiotherapy group, 27% of patients had testosterone levels below the reference range (8-35 nmol/L), compared with 10% of the nonirradiated patients (p <0.001). Irradiated patients had lower serum testosterone (mean, 11.1 vs. 13.4 nmol/L, p <0.001) and lower calculated free testosterone (mean, 214 vs. 235 pmol/L, p <0.05) than control subjects. Total testosterone, calculated free testosterone, and gonadotropins were related to the distance from the bony pelvic structures to the caudal field edge. Conclusions: Increased serum levels of gonadotropins and subnormal serum levels of testosterone indicate that curative radiotherapy for rectal cancer can result in permanent testicular dysfunction.

  3. Testosterone not associated with violent dreams or REM sleep behavior disorder in men with Parkinson's.

    PubMed

    Chou, Kelvin L; Moro-De-Casillas, Maria L; Amick, Melissa M; Borek, Leora L; Friedman, Joseph H

    2007-02-15

    We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD.

  4. Effect of orchiectomy and testosterone replacement on lower urinary tract function in anesthetized rats.

    PubMed

    Cheng, Chen-Li; de Groat, William C

    2016-11-01

    Lower urinary tract (LUT) symptoms (LUTS), including frequency, urgency, incomplete voiding, and slow stream, are common in both men and women with advancing age. The most common cause for LUTS in aging men is benign prostatic hyperplasia. Some studies have also revealed an inverse association of serum testosterone levels with LUTS; however, the underlying mechanisms by which gonadal hormones affect the LUT have not been clarified. In the present study, we examined the effect of orchiectomy and testosterone replacement on LUT function in adult male Sprague-Dawley rats. Six weeks after bilateral orchiectomy or sham operations and 3 wk after injection of long-acting testosterone undecanoate (100 mg/kg im), transvesical cystometry and external urethral sphincter electromyogram (EUS EMG) recordings were performed under urethane anesthesia. The micturition reflex was elicited in both sham and orchiectomized animals. In orchiectomized rats, volume threshold for inducing micturition decreased by 47.6%; however, contraction amplitude, duration, and voiding efficiency were similar in sham and orchiectomized rats. The active period during EUS EMG bursting was lengthened during micturition in orchiectomized animals. Testosterone treatment, which normalized plasma testosterone levels, reversed these changes but also increased the duration of EUS EMG bursting. Orchiectomy also reduced mean voiding flow rate estimated from the duration of EUS EMG bursting, an effect that was not reversed by testosterone. The results indicate that orchiectomy affects both the active and passive properties of the bladder and urethra, and that many, but not all, of the changes can be reversed by testosterone.

  5. Testosterone in human studies: Modest associations between plasma and salivary measurements.

    PubMed

    de Wit, A E; Bosker, F J; Giltay, E J; de Kloet, C S; Roelofs, K; van Pelt, J; Penninx, B W J H; Schoevers, R A

    2017-03-07

    Testosterone is involved in many processes like aggression and mood disorders. As it may easily diffuse from blood into saliva, salivary testosterone is thought to reflect plasma free testosterone level. If so, it would provide a welcome noninvasive and less stressful alternative to blood sampling. Past research did not reveal consensus regarding the strength of the association, but sample sizes were small. This study aimed to analyse the association in a large cohort. In total, 2,048 participants (age range 18-65 years; 696 males and 1,352 females) were included and saliva (using cotton Salivettes) and plasma were collected for testosterone measurements. Levels were determined by enzyme-linked immunosorbent assay and radioimmunoassay respectively. Free testosterone was calculated by the Vermeulen algorithm. Associations were determined using linear regression analyses. Plasma total and free testosterone showed a significant association with salivary testosterone in men (adjusted β = .09, p = .01; and β = .15, p < .001, respectively) and in women (adjusted β = .08, p = .004; and crude β = .09, p = .002 respectively). The modest associations indicate that there are many influencing factors of both technical and biological origin.

  6. Cortisol and testosterone increase financial risk taking and may destabilize markets.

    PubMed

    Cueva, Carlos; Roberts, R Edward; Spencer, Tom; Rani, Nisha; Tempest, Michelle; Tobler, Philippe N; Herbert, Joe; Rustichini, Aldo

    2015-07-02

    It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders' financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets. Specifically, we recorded salivary levels of cortisol and testosterone in people participating in an experimental asset market (N = 142) and found that individual and aggregate levels of endogenous cortisol predict subsequent risk-taking and price instability. We then administered either cortisol (single oral dose of 100 mg hydrocortisone, N = 34) or testosterone (three doses of 10 g transdermal 1% testosterone gel over 48 hours, N = 41) to young males before they played an asset trading game. We found that both cortisol and testosterone shifted investment towards riskier assets. Cortisol appears to affect risk preferences directly, whereas testosterone operates by inducing increased optimism about future price changes. Our results suggest that changes in both cortisol and testosterone could play a destabilizing role in financial markets through increased risk taking behaviour, acting via different behavioural pathways.

  7. Cortisol and testosterone increase financial risk taking and may destabilize markets

    PubMed Central

    Cueva, Carlos; Roberts, R. Edward; Spencer, Tom; Rani, Nisha; Tempest, Michelle; Tobler, Philippe N.; Herbert, Joe; Rustichini, Aldo

    2015-01-01

    It is widely known that financial markets can become dangerously unstable, yet it is unclear why. Recent research has highlighted the possibility that endogenous hormones, in particular testosterone and cortisol, may critically influence traders’ financial decision making. Here we show that cortisol, a hormone that modulates the response to physical or psychological stress, predicts instability in financial markets. Specifically, we recorded salivary levels of cortisol and testosterone in people participating in an experimental asset market (N = 142) and found that individual and aggregate levels of endogenous cortisol predict subsequent risk-taking and price instability. We then administered either cortisol (single oral dose of 100 mg hydrocortisone, N = 34) or testosterone (three doses of 10 g transdermal 1% testosterone gel over 48 hours, N = 41) to young males before they played an asset trading game. We found that both cortisol and testosterone shifted investment towards riskier assets. Cortisol appears to affect risk preferences directly, whereas testosterone operates by inducing increased optimism about future price changes. Our results suggest that changes in both cortisol and testosterone could play a destabilizing role in financial markets through increased risk taking behaviour, acting via different behavioural pathways. PMID:26135946

  8. Decreased prevalence of left-handedness among females with male co-twins: Evidence suggesting prenatal testosterone transfer in humans?

    PubMed Central

    Vuoksimaa, Eero; Peter Eriksson, C. J.; Pulkkinen, Lea; Rose, Richard J.; Kaprio, Jaakko

    2010-01-01

    Summary Studies of singletons suggest that right-handed individuals may have higher levels of testosterone than do left-handed individuals. Prenatal testosterone levels are hypothesised to be especially related to handedness formation. In humans, female members from opposite-sex twin pairs may experience elevated level of prenatal exposure to testosterone in their intra-uterine environment shared with a male. We tested for differences in rates of left-handedness/right-handedness in female twins from same-sex and opposite-sex twin pairs. Our sample consisted of 4736 subjects, about 70% of all Finnish twins born in 1983–1987, with information on measured pregnancy and birth related factors. Circulating testosterone and estradiol levels at age 14 were available on 771 and 744 of these twins, respectively. We found significantly (p<.006) lower prevalence of left-handedness in females from opposite-sex pairs (5.3%) compared to females from same-sex pairs (8.6%). The circulating levels of neither testosterone nor estradiol related to handedness in either females or males. Nor were there differences in circulating testosterone or estradiol levels between females from opposite-sex and same-sex twin pairs. Birth and pregnancy related factors for which we had information were unrelated to handedness. Our results are difficult to fully explain by postnatal factors, but they offer support to theory that relates testosterone to formation of handedness, and in a population-based sample, are suggestive of effects of prenatal testosterone transfer. PMID:20570052

  9. Decreased prevalence of left-handedness among females with male co-twins: evidence suggesting prenatal testosterone transfer in humans?

    PubMed

    Vuoksimaa, Eero; Eriksson, C J Peter; Pulkkinen, Lea; Rose, Richard J; Kaprio, Jaakko

    2010-11-01

    Studies of singletons suggest that right-handed individuals may have higher levels of testosterone than do left-handed individuals. Prenatal testosterone levels are hypothesised to be especially related to handedness formation. In humans, female members from opposite-sex twin pairs may experience elevated level of prenatal exposure to testosterone in their intrauterine environment shared with a male. We tested for differences in rates of left-handedness/right-handedness in female twins from same-sex and opposite-sex twin pairs. Our sample consisted of 4736 subjects, about 70% of all Finnish twins born in 1983-1987, with information on measured pregnancy and birth related factors. Circulating testosterone and estradiol levels at age 14 were available on 771 and 744 of these twins, respectively. We found significantly (p=.006) lower prevalence of left-handedness in females from opposite-sex pairs (5.3%) compared to females from same-sex pairs (8.6%). The circulating levels of neither testosterone nor estradiol related to handedness in either females or males. Nor were there differences in circulating testosterone or estradiol levels between females from opposite-sex and same-sex twin pairs. Birth and pregnancy related factors for which we had information were unrelated to handedness. Our results are difficult to fully explain by postnatal factors, but they offer support to theory that relates testosterone to formation of handedness, and in a population-based sample, are suggestive of effects of prenatal testosterone transfer.

  10. Pretreatment Serum Testosterone and Androgen Deprivation: Effect on Disease Recurrence and Overall Survival in Prostate Cancer Patients Treated With Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Lief, Jonathan H.; Adamovich, Edward

    2009-07-15

    Purpose: Low testosterone has been implicated as a possible adverse prognostic factor in patients with newly diagnosed prostate cancer. We evaluated the impact of pretreatment serum testosterone on survival after prostate brachytherapy. Methods and Materials: From October 2001 to November 2004, 619 patients underwent brachytherapy and 546 had a pretreatment serum testosterone level measured. Pretreatment serum testosterone levels were assigned by the following criteria: below-normal (n = 105), low normal (n = 246), mid normal (n = 132), high normal (n = 50), and above normal (n = 13). Median follow-up was 5.2 years. Cause of death was determined for each deceased patient. Results: Six-year biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were 97.7%, 99.8%, and 89.2%. When comparing patients with low or low normal testosterone with those with average or higher testosterone, there was no significant difference in bPFS (97.6% vs. 98.4%; p = 0.72), CSS (99.8% vs. 100%; p = 0.72), or OS (88.9% vs. 90.8%; p = 0.73). Among patients with average and higher pretreatment testosterone, there was no significant difference in outcomes when comparing patients who did and did not receive androgen deprivation therapy (ADT). For patients with low or low normal testosterone levels, there was no significant difference in bPFS or CSS when comparing patients who did and did not receive ADT. However, there was a trend toward lower OS in patients with baseline lower testosterone levels who also received ADT (83.9% vs. 91.3%, p = 0.075). Conclusions: Low pretreatment testosterone levels alone did not affect disease recurrence or OS. Patients with baseline low testosterone who also were treated with ADT had a trend toward decreased OS.

  11. [Testosterone replacement therapy and prostate cancer: the downfall of a paradigm?].

    PubMed

    Castillo, Octavio A; López-Fontana, Gastón; Vidal-Mora, Ivar; López Laur, José Daniel

    2015-04-06

    For six decades, it has been a part of the conventional medical wisdom that higher levels of testosterone increase the risk of prostate cancer. This belief is mostly derived from the well-documented regression of prostate cancer after surgical or pharmacological castration. However, there is an absence of scientific data supporting the concept that higher testosterone levels are associated with an increased risk of prostate cancer. Moreover, men with hypogonadism have substantial rates of prostate cancer in prostatic biopsies, suggesting that low testosterone has no protective effect against the development of prostate cancer. Moreover, prostate cancer rate is higher in elderly patients when hormonal levels are low. These results argue against an increased risk of prostate cancer with testosterone replacement therapy.

  12. Bioavailable level and source of cysteine determine protein quality of a commercial enteral product: adequacy of tryptophan but deficiency of cysteine for rats fed an enteral product prepared fresh or stored beyond shelf life.

    PubMed

    Baker, D H; Han, Y

    1993-03-01

    Young rats were used in bioassays designed to assess the protein quality and tryptophan as well as cystine adequacy of the enteral product TwoCal-HN that was either freshly prepared or had been stored (nonrefrigerated) in a warehouse for 10 mo (i.e., beyond shelf life). Based upon supplementation studies, cystine was observed to be the first-limiting amino acid in both fresh and expired TwoCal-HN, and tryptophan was not second limiting. Protein efficiency ratio (PER) of expired, but not fresh, TwoCal-HN was lower than that of the casein control diet, but with cystine supplementation, PER of the TwoCal-HN products was equal to or greater than the PER of the casein control. With a diet containing 10 g protein/100 g that also contained energy-furnishing ingredients simulating TwoCal-HN, maximal growth enhancement occurred with a supplement of 1 g cystine/kg diet. Both glutathione and N-acetyl-L-cysteine were observed to be equivalent to an isomolar level of L-cystine in stimulating growth. Using a chemically defined amino acid diet that was singly deficient in tryptophan, bioavailability of tryptophan was determined for casein, fresh TwoCal-HN, expired TwoCal-HN and D-tryptophan. Slope-ratio bioefficacy values relative to L-tryptophan (weight gain regressed on supplemental tryptophan intake) indicated that none of the experimental sources of tryptophan had bioavailabilities different from 100%. The results indicated that tryptophan did not deteriorate, as measured analytically or biologically, as a result of storing TwoCal-HN beyond shelf life.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Plasma testosterone in male patients with Huntington's disease: relations to severity of illness and dementia.

    PubMed

    Markianos, Manolis; Panas, Marios; Kalfakis, Nikos; Vassilopoulos, Dimitrios

    2005-04-01

    Huntington's disease (HD) is a neurodegenerative disorder characterized by motor, cognitive, and psychiatric symptoms and by a progressive loss among other, of dopaminergic receptors in striatum, cortex, and hypothalamus. Central dopaminergic activity has been implicated in the regulation of sex hormones. Several features of testosterone deficiency, such as reduced muscle mass, depressive mood, and cognitive impairment, are often present in HD patients, but data on their testosterone levels are lacking. We assessed plasma levels of testosterone, LH, and FSH in 42 male patients with HD, confirmed by molecular genetic analysis, and searched for differences from age-matched healthy male subjects and for relations to CAG repeat number, age, age range, 26 to 76 (mean, 50.7 +/- 12.3) years; duration of illness range, 1 to 23 (mean, 6.7 +/- 6.3) years; and CAG repeat numbers from 40 to 65 (45.1 +/- 3.8). Disease symptomatology was assessed using the Unified Huntington's Disease Rating Scale. Testosterone and LH levels of the patients were significantly lower compared to the levels of 44 age-matched (mean age, 48.9 +/- 13.0, range, 26-76 years) healthy men. Severity of illness was negatively related to plasma testosterone levels. Further, low testosterone levels were associated with dementia but not with depression or psychotic features. Clinical studies with selected HD patients are needed to evaluate possible beneficial effects of androgen substitution therapy on cognitive functions, depression, muscle mass and strength, general well-being, and, eventually, neuroprotective effects.

  14. Lack of evidence for meteorological effects on infradian dynamics of testosterone

    NASA Astrophysics Data System (ADS)

    Celec, Peter; Smreková, Lucia; Ostatníková, Daniela; Čabajová, Zlata; Hodosy, Július; Kúdela, Matúš

    2009-09-01

    Climatic factors are known to influence the endocrine system. Previous studies have shown that circannual seasonal variations of testosterone might be partly explained by changes in air temperature. Whether infradian variations are affected by meteorological factors is unknown. To analyze possible effects of meteorological parameters on infradian variations of salivary testosterone levels in both sexes, daily salivary testosterone levels were measured during 1 month in 14 men and 17 women. A correlation analysis between hormonal levels and selected meteorological parameters was performed. The results indicate that high testosterone levels are loosely associated with cold, sunny and dry weather in both sexes. However, only the correlations between testosterone and air temperature (men) and actual cloudiness (women) were statistically significant ( p < 0,05). Although some correlations reached the level of statistical significance, the effects of selected meteorological parameters on salivary testosterone levels remain unclear. Further longer-term studies concentrating on air temperature, cloudiness and average relative humidity in relation to the sex hormone axis are needed.

  15. Testosterone Replacement Therapy and BPH/LUTS. What is the Evidence?

    PubMed

    Baas, Wesley; Köhler, Tobias S

    2016-06-01

    Contrary to the previous dogma that prostatic growth is directly proportional to testosterone levels, emerging research has suggested a lack of testosterone may be a risk factor for lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH). Within this review article, we have demonstrated the current understanding of the physiology of hypogonadism and its interplay with prostatic and lower urinary tract physiology. The current evidence suggests that not only does testosterone replacement therapy (TRT) not worsen LUTS, but that hypogonadism itself is an important risk factor for LUTS/BPH.

  16. Bioavailability of Cadmium in Inexpensive Jewelry

    PubMed Central

    Miller, Jennifer; Guinn, Daphne; Pearson, Janna

    2011-01-01

    Objectives: We evaluated the bioavailability of Cd in 86 components of 57 jewelry items found to contain high levels of Cd (> 10,000 ppm) by X-ray fluorescence (XRF), using extractions that simulate mouthing or swallowing of jewelry items. Methods: We screened jewelry for Cd content by XRF. Bioavailability was measured in two ways. Items were placed in saline solution at 37°C for 6 hr to simulate exposures from mouthing of jewelry items. Items were placed in dilute hydrochloric acid (HCl) at 37°C for 6–96 hr, simulating the worst-case scenario of a child swallowing a jewelry item. Damaged pieces of selected samples were also extracted by both methods to determine the effect of breaching the outer plating on bioavailability. Total Cd content of all items was determined by atomic absorption. Results: The 6-hr saline extraction yielded as much as 2,200 µg Cd, and 24-hr dilute HCl extraction yielded a maximum of > 20,000 µg Cd. Leaching of Cd in dilute HCl increased linearly over 6–96 hr, indicating potential for increasing harm the longer an item remains in the stomach. Damage to jewelry by breaching the outer plating generally, but not always, increased Cd release. Bioavailability did not correlate directly with Cd content. Conclusions: These results indicate the potential for dangerous Cd exposures to children who wear, mouth, or accidentally swallow high-Cd jewelry items. PMID:21377949

  17. Association of androgen with gender difference in serum adipocyte fatty acid binding protein levels

    PubMed Central

    Hu, Xiang; Ma, Xiaojing; Pan, Xiaoping; Luo, Yuqi; Xu, Yiting; Xiong, Qin; Bao, Yuqian; Jia, Weiping

    2016-01-01

    Clinical investigations have indicated women have higher levels of adipocyte fatty acid binding protein (A-FABP) than men. The present study aimed to identify factors related to gender difference in serum A-FABP levels. A total of 507 participants (194 men, 132 premenopausal women, and 181 postmenopausal women) were enrolled in the present study. Serum A-FABP levels increased in the order from men to premenopausal women to postmenopausal women in both body mass index categories (<25.0 and ≥25.0 kg/m2; all P < 0.05). Multiple stepwise regression analyses showed that after adjustment for factors related to serum A-FABP levels, the trunk fat mass was an independent and positive factor of serum A-FABP levels. For men, total testosterone was associated independently and inversely with serum A-FABP levels. For pre- and postmenopausal women, bioavailable testosterone and total testosterone were independent and positive factors associated with serum A-FABP levels, respectively. The present study demonstrated that the androgen was correlated with the serum A-FABP levels negatively in men, but positively in women. With these effects on the fat content, especially trunk fat, androgen might contribute to the gender difference in serum A-FABP levels. PMID:27270834

  18. Testosterone, Marital Quality, and Role Overload

    ERIC Educational Resources Information Center

    Booth, Alan; Johnson, David R.; Granger, Douglas A.

    2005-01-01

    In a sample of established working- and middle-class families with school-aged children (N= 307 wives and 307 husbands), neither husbands nor wives testosterone showed a direct connection with marital quality. In contrast, the association between husbands' testosterone and positive and negative marital quality (as evaluated by both spouses) was…

  19. Elevated Testosterone Reduces Uterine Blood Flow, Spiral Artery Elongation, and Placental Oxygenation in Pregnant Rats.

    PubMed

    Gopalakrishnan, Kathirvel; Mishra, Jay S; Chinnathambi, Vijayakumar; Vincent, Kathleen L; Patrikeev, Igor; Motamedi, Massoud; Saade, George R; Hankins, Gary D; Sathishkumar, Kunju

    2016-03-01

    Elevated maternal testosterone levels are shown to cause fetal growth restriction, eventually culminating in sex-specific adult-onset hypertension that is more pronounced in males than in females. In this study, we tested whether uteroplacental and fetoplacental disturbances underlie fetal growth restriction and if these changes vary in male and female placentas. Pregnant Sprague-Dawley rats were injected with vehicle (n=16) or testosterone propionate (0.5 mg/kg per day from gestation day 15-19; n=16). On gestation day 20, we quantified uterine artery blood flow using microultrasound, visualized placental arterial network using x-ray microcomputed tomography, determined fetoplacental hypoxia using pimonidazole and hypoxia-inducible factor-1α, and used Affymetrix array to determine changes in placental expression of genes involved in vascular development. Plasma testosterone levels increased 2-fold in testosterone-injected rats. Placental and fetal weights were lower in rats with elevated testosterone. Uterine artery blood flow was lower, and resistance index was higher in the testosterone group. Radial and spiral artery diameter and length, the number of fetoplacental arterial branches, and umbilical artery diameter were reduced in the testosterone group. In addition, markers of hypoxia in the placentas and fetuses were elevated in the testosterone group. The magnitude of changes in placental vasculature and hypoxia was greater in males than in females and was associated with sex-specific alteration of unique sets of genes involved in angiogenesis and blood vessel morphogenesis. The results demonstrate that elevated testosterone during gestation induces a decrease in uterine arterial blood flow and fetal sex-related uteroplacental vascular changes, which may set the stage for subsequent sex differences in adult-onset diseases.

  20. Effects of testosterone replacement in men with opioid-induced androgen deficiency: a randomized controlled trial.

    PubMed

    Basaria, Shehzad; Travison, Thomas G; Alford, Daniel; Knapp, Philip E; Teeter, Kjersten; Cahalan, Christine; Eder, Richard; Lakshman, Kishore; Bachman, Eric; Mensing, George; Martel, Marc O; Le, Dillon; Stroh, Helene; Bhasin, Shalender; Wasan, Ajay D; Edwards, Robert R

    2015-02-01

    Symptomatic androgen deficiency is common in patients taking opioid analgesics, as these drugs potently suppress the hypothalamic-pituitary-gonadal axis. However, the efficacy of testosterone replacement in this setting remains unclear. The objective of this trial was to evaluate the efficacy of testosterone replacement on pain perception and other androgen-dependent outcomes in men with opioid-induced androgen deficiency. We conducted a randomized, double-blind, parallel placebo-controlled trial at an outpatient academic research center. Participants were men aged 18 to 64 years on opioid analgesics for chronic noncancer pain, and total testosterone levels were <350 ng/dL. Participants were randomly assigned to 14 weeks of daily transdermal gel that contained 5 g of testosterone or placebo. Primary outcomes were changes in self-reported clinical pain and objectively assessed pain sensitivity. Sexual function, quality of life, and body composition were also assessed. The mean age was 49 years. The median total and free testosterone levels at baseline were 243 ng/dL and 47 pg/mL and 251 ng/dL and 43 pg/mL in the testosterone and placebo arm, respectively. Of the 84 randomized participants, 65 had follow-up data on efficacy outcomes. Compared with men assigned to the placebo arm, those assigned to testosterone replacement experienced greater improvements in pressure and mechanical hyperalgesia, sexual desire, and role limitation due to emotional problems. Testosterone administration was also associated with an improvement in body composition. There were no between-group differences in changes in self-reported pain. In conclusion, in men with opioid-induced androgen deficiency, testosterone administration improved pain sensitivity, sexual desire, body composition, and aspects of quality of life.

  1. Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards (Uta stansburiana)

    PubMed Central

    LaDage, Lara D.; Roth, Timothy C.; Downs, Cynthia J.; Sinervo, Barry; Pravosudov, Vladimir V.

    2017-01-01

    Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial—defending large, clearly defined spatial boundaries—or non-territorial—traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer

  2. Increased Testosterone Decreases Medial Cortical Volume and Neurogenesis in Territorial Side-Blotched Lizards (Uta stansburiana).

    PubMed

    LaDage, Lara D; Roth, Timothy C; Downs, Cynthia J; Sinervo, Barry; Pravosudov, Vladimir V

    2017-01-01

    Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorial-defending large, clearly defined spatial boundaries-or non-territorial-traversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer doublecortin

  3. ELEVATED TESTOSTERONE REDUCES UTERINE BLOOD FLOW, SPIRAL ARTERY ELONGATION AND PLACENTAL OXYGENATION IN PREGNANT RATS

    PubMed Central

    Gopalakrishnan, Kathirvel; Mishra, Jay S.; Chinnathambi, Vijayakumar; Vincent, Kathleen L.; Patrikeev, Igor; Motamedi, Massoud; Saade, George R.; Hankins, Gary D.; Sathishkumar, Kunju

    2016-01-01

    Elevated maternal testosterone levels are shown to cause fetal growth restriction, eventually culminating in sex-specific adult-onset hypertension that is more pronounced in males than females. In this study, we tested whether utero- and feto-placental disturbances underlie fetal growth restriction and if these changes vary in male and female placentas. Pregnant Sprague-Dawley rats were injected with vehicle (n=16) or testosterone propionate (0.5 mg/Kg/day from gestation day 15–19; n=16). On gestation day 20, we quantified uterine artery blood flow using microultrasound, visualized placental arterial network using x-ray microcomputed tomography, determined fetoplacental hypoxia using pimonidazole and hypoxia-inducible factor-1α, and used Affymetrix array to determine changes in placental expression of genes involved in vascular development. Plasma testosterone levels increased 2-fold in testosterone-injected rats. Placental and fetal weights were lower in rats with elevated testosterone. Uterine artery blood flow was lower and resistance index was higher in testosterone group. Radial and spiral artery diameter and length, number of fetoplacental arterial branches, and umbilical artery diameter were reduced in the testosterone group. In addition, markers of hypoxia in the placentas and fetuses were elevated in the testosterone group. The magnitude of changes in placental vasculature and hypoxia were greater in males than females and were associated with sex-specific alteration of unique sets of genes involved in angiogenesis and blood vessel morphogenesis. The results demonstrate that elevated testosterone during gestation induces a decrease in uterine arterial blood flow and fetal sex-related uteroplacental vascular changes, which may set the stage for subsequent sex differences in adult-onset diseases. PMID:26781277

  4. Testosterone

    MedlinePlus

    ... RL, Barnes RB, Ehrmann DA. Hyperandrogenism, hirsuitism, and polycystic ovary syndrome. In: Jameson JL, De Groot LJ, de Kretser ... Hypopituitarism Luteinizing hormone (LH) blood test Ovarian cancer Polycystic ovary syndrome Precocious puberty Prolactinoma Testicular cancer Testicular failure Review ...

  5. Lack of sexual activity from erectile dysfunction is associated with a reversible reduction in serum testosterone.

    PubMed

    Jannini, E A; Screponi, E; Carosa, E; Pepe, M; Lo Giudice, F; Trimarchi, F; Benvenga, S

    1999-12-01

    The role of androgenic hormones in human sexuality, in the mechanism of erection and in the pathogenesis of impotence is under debate. While the use of testosterone is common in the clinical therapy of male erectile dysfunction, hypogonadism is a rare cause of impotence. We evaluated serum testosterone levels in men with erectile dysfunction resulting either from organic or non-organic causes before and after non-hormonal impotence therapy. Eighty-three consecutive cases of impotence (70% organic, 30% non-organic, vascular aetiology being the most frequent) were subjected to hormonal screening before and after various psychological, medical (prostaglandin E1, yohimbine) or mechanical therapies (vascular surgery, penile prostheses, vacuum devices). Thirty age-matched healthy men served as a control group. Compared to controls, patients with impotence resulting from both organic and non-organic causes showed reduced serum levels of both total testosterone (11.1 +/- 2.4 vs. 17.7 +/- 5.5 nmol/L) and free testosterone (56.2 +/- 22.9 vs. 79.4 +/- 27.0 pmol/L) (both p < 0.001). Irrespective of the different aetiologies and of the various impotence therapies, a dramatic increase in serum total and free testosterone levels (15.6 +/- 4.2 nmol/L and 73.8 +/- 22.5 pmol/L, respectively) was observed in patients who achieved normal sexual activity 3 months after commencing therapy (p < 0.001). On the contrary, serum testosterone levels did not change in patients in whom therapies were ineffective. Since the pre-therapy low testosterone levels were independent of the aetiology of impotence, we hypothesize that this hormonal pattern is related to the loss of sexual activity, as demonstrated by its normalization with the resumption of coital activity after different therapies. The corollary is that sexual activity may feed itself throughout the increase in testosterone levels.

  6. Modeling Testosterone Circadian Rhythm in Hypogonadal Males: Effect of Age and Circannual Variations.

    PubMed

    González-Sales, Mario; Barrière, Olivier; Tremblay, Pierre-Olivier; Nekka, Fahima; Desrochers, Julie; Tanguay, Mario

    2016-01-01

    The objective of this study was to characterize the baseline circadian rhythm of testosterone levels in hypogonadal men. A total of 859 baseline profiles of testosterone from hypogonadal men were included in this analysis. The circadian rhythm of the testosterone was described by a stretched cosine function. Model parameters were estimated using NONMEM(®) 7.3. The effect of different covariates on the testosterone levels was investigated. Model evaluation was performed using non-parametric bootstrap and predictive checks. A stretched cosine function deeply improved the data goodness of fit compared to the standard trigonometric function (p < 0.001; ΔOFV = -204). The effect of the age and the semester, defined as winter and spring versus summer and fall, were significantly associated with the baseline levels of testosterone (p < 0.001, ΔOFV = -15.6, and p < 0.001, ΔOFV = -47.0). Model evaluation procedures such as diagnostic plots, visual predictive check, and non-parametric bootstrap evidenced that the proposed stretched cosine function was able to model the time course of the diurnal testosterone levels in hypogonadal males with accuracy and precision. The circadian rhythm of the testosterone levels was better predicted by the proposed stretched cosine function than a standard cosine function. Testosterone levels decreased by 5.74 ng/dL (2.4%) every 10 years and were 19.3 ng/dL (8.1%) higher during winter and spring compared to summer and fall.

  7. Testosterone Replacement Therapy and the Cardiovascular System.

    PubMed

    Naderi, Sahar

    2016-04-01

    As testosterone replacement therapy (TRT) has emerged as a commonly prescribed therapy for symptomatic low testosterone, conflicting data have been reported in terms of both its efficacy and potential adverse outcomes. One of the most controversial associations has been that of TRT and cardiovascular morbidity and mortality. This review briefly provides background on the history of TRT, the indications for TRT, and the data behind TRT for symptomatic low testosterone. It then specifically delves into the rather limited data for cardiovascular outcomes of those with low endogenous testosterone and those who receive TRT. The available body of literature strongly suggests that more work, by way of clinical trials, needs to be done to better understand the impact of testosterone and TRT on the cardiovascular system.

  8. Drug Insight: testosterone and selective androgen receptor modulators as anabolic therapies for chronic illness and aging

    PubMed Central

    Bhasin, Shalender; Calof, Olga M; Storer, Thomas W; Lee, Martin L; Mazer, Norman A; Jasuja, Ravi; Montori, Victor M; Gao, Wenqing; Dalton, James T

    2007-01-01

    SUMMARY Several regulatory concerns have hindered development of androgens as anabolic therapies, despite unequivocal evidence that testosterone supplementation increases muscle mass and strength in men; it induces hypertrophy of type I and II muscle fibers, and increases myonuclear and satellite cell number. Androgens promote differentiation of mesenchymal multipotent cells into the myogenic lineage and inhibit their adipogenic differentiation, by facilitating association of androgen receptors with β-catenin and activating T-cell factor 4. Meta-analyses indicate that testosterone supplementation increases fat-free mass and muscle strength in HIV-positive men with weight loss, glucocorticoid-treated men, and older men with low or low-normal testosterone levels. The effects of testosterone on physical function and outcomes important to patients have not, however, been studied. In older men, increased hematocrit and increased risk of prostate biopsy and detection of prostate events are the most frequent, testosterone-related adverse events. Concerns about long-term risks have restrained enthusiasm for testosterone use as anabolic therapy. Selective androgen-receptor modulators that are preferentially anabolic and that spare the prostate hold promise as anabolic therapies. We need more studies to determine whether testosterone or selective androgen-receptor modulators can induce meaningful improvements in physical function and patient-important outcomes in patients with physical dysfunction associated with chronic illness or aging. PMID:16932274

  9. No Association between the 2D:4D Fetal Testosterone Marker and Multidimensional Attentional Abilities in Children with ADHD

    ERIC Educational Resources Information Center

    Lemiere, Jurgen; Boets, Bart; Danckaerts, Marina

    2010-01-01

    Aim: It has been suggested that high levels of prenatal testosterone exposure are implied in the aetiology of attention-deficit-hyperactivity disorder (ADHD). This study examined the association between the ratio of the length of the second and fourth digits (2D:4D ratio), a marker of fetal testosterone exposure, and the presence of ADHD-related…

  10. Relationship between androgen levels and blood pressure in young women with polycystic ovary syndrome.

    PubMed

    Chen, Mei-Jou; Yang, Wei-Shiung; Yang, Jehn-Hsiahn; Chen, Chi-Ling; Ho, Hong-Nerng; Yang, Yu-Shih

    2007-06-01

    The role of testosterone on the development of hypertension is controversial, especially in women with polycystic ovary syndrome (PCOS) who have higher prevalence of obesity and insulin resistance than women without PCOS. Little is known about the association between serum testosterone level and blood pressure in young women with PCOS. In the 151 young Taiwanese women with PCOS enrolled in this cross-sectional study, we measured the body mass index, waist circumference, blood pressure, fasting glucose, fasting insulin, lipid profile, and hormone profiles. The free androgen index, total testosterone, and sex hormone-binding globulin, but not the level of dehydroepiandrosterone sulfate, significantly correlated with both systolic blood pressure (SBP) and diastolic blood pressure (DBP). In multiple linear regression models adjusted for age, body mass index, and other anthropometric, metabolic, and hormonal variables, the level of serum free androgen index or total testosterone, but not the sex hormone-binding globulin, were independently related to SBP and DBP. The age- and body mass index-adjusted least-square mean of serum-free androgen index levels were significantly different between the highest quartile and other quartiles of the SBP and DBP levels. The high bioavailable testosterone levels (free androgen index: >or=19%) in women with PCOS increased the risk of elevated blood pressure (SBP >or=130 mm Hg and/or DBP >or=85 mm Hg) with an odds ratio of 3.817 (P=0.029; 95% CI: 1.14 to 12.74) after adjustment for age, anthropometric measures, and metabolic profiles. Our results suggest that the characteristic hyperandrogenemia in young women with PCOS was associated with an elevated SBP and DBP independent of age, insulin resistance, obesity, or dyslipidemia.

  11. Relationships among musical aptitude, digit ratio and testosterone in men and women.

    PubMed

    Borniger, Jeremy C; Chaudhry, Adeel; Muehlenbein, Michael P

    2013-01-01

    Circulating adult testosterone levels, digit ratio (length of the second finger relative to the fourth finger), and directional asymmetry in digit ratio are considered sexually dimorphic traits in humans. These have been related to spatial abilities in men and women, and because similar brain structures appear to be involved in both spatial and musical abilities, neuroendocrine function may be related to musical as well as spatial cognition. To evaluate relationships among testosterone and musical ability in men and women, saliva samples were collected, testosterone concentrations assessed, and digit ratios calculated using standardized protocols in a sample of university students (N = 61), including both music and non-music majors. Results of Spearman correlations suggest that digit ratio and testosterone levels are statistically related to musical aptitude and performance only within the female sample: A) those females with greater self-reported history of exposure to music (p = 0.016) and instrument proficiency (p = 0.040) scored higher on the Advanced Measures of Music Audiation test, B) those females with higher left hand digit ratio (and perhaps lower fetal testosterone levels) were more highly ranked (p = 0.007) in the orchestra, C) female music students exhibited a trend (p = 0.082) towards higher testosterone levels compared to female non-music students, and D) female music students with higher rank in the orchestra/band had higher testosterone levels (p = 0.003) than lower ranked students. None of these relationships were significant in the male sample, although a lack of statistical power may be one cause. The effects of testosterone are likely a small part of a poorly understood system of biological and environmental stimuli that contribute to musical aptitude. Hormones may play some role in modulating the phenotype of musical ability, and this may be the case for females more so than males.

  12. Relationships among Musical Aptitude, Digit Ratio and Testosterone in Men and Women

    PubMed Central

    Borniger, Jeremy C.; Chaudhry, Adeel; Muehlenbein, Michael P.

    2013-01-01

    Circulating adult testosterone levels, digit ratio (length of the second finger relative to the fourth finger), and directional asymmetry in digit ratio are considered sexually dimorphic traits in humans. These have been related to spatial abilities in men and women, and because similar brain structures appear to be involved in both spatial and musical abilities, neuroendocrine function may be related to musical as well as spatial cognition. To evaluate relationships among testosterone and musical ability in men and women, saliva samples were collected, testosterone concentrations assessed, and digit ratios calculated using standardized protocols in a sample of university students (N = 61), including both music and non-music majors. Results of Spearman correlations suggest that digit ratio and testosterone levels are statistically related to musical aptitude and performance only within the female sample: A) those females with greater self-reported history of exposure to music (p = 0.016) and instrument proficiency (p = 0.040) scored higher on the Advanced Measures of Music Audiation test, B) those females with higher left hand digit ratio (and perhaps lower fetal testosterone levels) were more highly ranked (p = 0.007) in the orchestra, C) female music students exhibited a trend (p = 0.082) towards higher testosterone levels compared to female non-music students, and D) female music students with higher rank in the orchestra/band had higher testosterone levels (p = 0.003) than lower ranked students. None of these relationships were significant in the male sample, although a lack of statistical power may be one cause. The effects of testosterone are likely a small part of a poorly understood system of biological and environmental stimuli that contribute to musical aptitude. Hormones may play some role in modulating the phenotype of musical ability, and this may be the case for females more so than males. PMID:23520475

  13. Testosterone and Cortisol Release among Spanish Soccer Fans Watching the 2010 World Cup Final

    PubMed Central

    van der Meij, Leander; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; IJzerman, Hans; van Lange, Paul A. M.; Salvador, Alicia

    2012-01-01

    This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, but the increase in total cortisol secretion during the match was higher among men than among women and among fans that were younger. Also, increases in cortisol secretion were greater to the degree that people were a stronger fan of soccer. Level of fandom further appeared to account for the sex effect, but not for the age effect. Generally, the testosterone data from this study are in line with the challenge hypothesis, as testosterone levels of watchers increased to prepare their organism to defend or enhance their social status. The cortisol data from this study are in line with social self-preservation theory, as higher cortisol secretion among young and greater soccer fans suggests that especially they perceived that a negative outcome of the match would threaten their own social esteem. PMID:22529940

  14. Testosterone and cortisol release among Spanish soccer fans watching the 2010 World Cup final.

    PubMed

    van der Meij, Leander; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; Ijzerman, Hans; van Lange, Paul A M; Salvador, Alicia

    2012-01-01

    This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, but the increase in total cortisol secretion during the match was higher among men than among women and among fans that were younger. Also, increases in cortisol secretion were greater to the degree that people were a stronger fan of soccer. Level of fandom further appeared to account for the sex effect, but not for the age effect. Generally, the testosterone data from this study are in line with the challenge hypothesis, as testosterone levels of watchers increased to prepare their organism to defend or enhance their social status. The cortisol data from this study are in line with social self-preservation theory, as higher cortisol secretion among young and greater soccer fans suggests that especially they perceived that a negative outcome of the match would threaten their own social esteem.

  15. Investigating the binding behaviour of two avidin-based testosterone binders using molecular recognition force spectroscopy.

    PubMed

    Rangl, Martina; Leitner, Michael; Riihimäki, Tiina; Lehtonen, Soili; Hytönen, Vesa P; Gruber, Hermann J; Kulomaa, Markku; Hinterdorfer, Peter; Ebner, Andreas

    2014-02-01

    Molecular recognition force spectroscopy, a biosensing atomic force microscopy technique allows to characterise the dissociation of ligand-receptor complexes at the molecular level. Here, we used molecular recognition force spectroscopy to study the binding capability of recently developed testosterone binders. The two avidin-based proteins called sbAvd-1 and sbAvd-2 are expected to bind both testosterone and biotin but differ in their binding behaviour towards these ligands. To explore the ligand binding and dissociation energy landscape of these proteins, we tethered biotin or testosterone to the atomic force microscopy probe while the testosterone-binding protein was immobilized on the surface. Repeated formation and rupture of the ligand-receptor complex at different pulling velocities allowed determination of the loading rate dependence of the complex-rupturing force. In this way, we obtained the molecular dissociation rate (k(off)) and energy landscape distances (x(β)) of the four possible complexes: sbAvd-1-biotin, sbAvd-1-testosterone, sbAvd-2-biotin and sbAvd-2-testosterone. It was found that the kinetic off-rates for both proteins and both ligands are similar. In contrast, the x(β) values, as well as the probability of complex formations, varied considerably. In addition, competitive binding experiments with biotin and testosterone in solution differ significantly for the two testosterone-binding proteins, implying a decreased cross-reactivity of sbAvd-2. Unravelling the binding behaviour of the investigated testosterone-binding proteins is expected to improve their usability for possible sensing applications.

  16. Prevalence of Low Testosterone and Predisposing Risk Factors in Men With Type 1 Diabetes Mellitus: Findings From the DCCT/EDIC

    PubMed Central

    Holt, Sarah K.; Lopushnyan, Natalya; Hotaling, James; Sarma, Aruna V.; Dunn, Rodney L.; Cleary, Patricia A.; Braffett, Barbara H.; Gatcomb, Patricia; Martin, Catherine; Herman, William H.

    2014-01-01

    Context: Previous studies have demonstrated lower testosterone concentrations in men with type 2 diabetes mellitus. Data in men with type 1 diabetes mellitus (T1DM) are limited. Objective: Our objective was to determine the prevalence of low testosterone in men with T1DM and identify predisposing factors. Design, Setting, and Participants: This was a cross-sectional study of men with T1DM participating in UroEDIC (n = 641), an ancillary study of urologic complications in the Epidemiology of Diabetes Interventions and Complications (EDIC). Main Outcome Measures: Total serum testosterone levels were measured using mass spectrometry, and SHBG levels were measured using sandwich immunoassay on samples from EDIC year 17/18. Calculated free testosterone was determined using an algorithm incorporating binding constants for albumin and SHBG. Low testosterone was defined as total testosterone <300 mg/dL. Multivariate regression models were used to compare age, body mass index, factors related to diabetes treatment and control, and diabetic complications with testosterone levels. Results: Mean age was 51 years. Sixty-one men (9.5%) had testosterone <300 mg/dL. Decreased testosterone was significantly associated with obesity (P < .01), older age (P < .01) and decreased SHBG (P < .001). Insulin dose was inversely associated with calculated free testosterone (P = .02). Hypertension retained a significant adjusted association with lower testosterone (P = .05). There was no observed significant relationship between lower testosterone and nephropathy, peripheral neuropathy, and autonomic neuropathy measures. Conclusion: The men with T1DM in the EDIC cohort do not appear to have a high prevalence of androgen deficiency. Risk factors associated with low testosterone levels in this population are similar to the general population. PMID:25013994

  17. Salivary testosterone as a potential indicator for risky behaviour associated with smoking-related peer pressure in adolescents.

    PubMed

    Idris, Adi; Ghazali, Nur B; Said, Nadzirah M; Steele, Michael; Koh, David; Tuah, Nik A

    2016-04-09

    Early smoking is considered an indicator for risky behaviour in adolescents. Although social indicators predicting adolescent smoking are known, biological indicators have not been defined. This study aimed to establish whether salivary testosterone could be used as a "predictive biomarker" for smoking-associated peer pressure. Saliva samples were collected from Bruneian adolescents (aged 13-17 years) by the passive drool method. Salivary testosterone concentration was determined by enzyme-linked immunosorbent assay. Salivary testosterone concentration and smoking-associated peer pressure indicators were compared between adolescent males and females and statistical significance was determined by an independent samples t-test. A significant positive relationship between smoking-associated peer pressure and salivary testosterone levels in adolescents was found. However, this relationship was not significant when males and females were considered separately. Our data suggest that students who have tried cigarette smoking and have friends who are cigarette smokers have higher salivary testosterone levels.

  18. Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice

    PubMed Central

    Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

    2016-01-01

    Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg−1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo. PMID:26608944

  19. Effects of velvet antler polypeptide on sexual behavior and testosterone synthesis in aging male mice.

    PubMed

    Zang, Zhi-Jun; Tang, Hong-Feng; Tuo, Ying; Xing, Wei-Jie; Ji, Su-Yun; Gao, Yong; Deng, Chun-Hua

    2016-01-01

    Twenty-four-month-old male C57BL/6 mice with low serum testosterone levels were used as a late-onset hypogonadism (LOH) animal model for examining the effects of velvet antler polypeptide (VAP) on sexual function and testosterone synthesis. These mice received VAP for 5 consecutive weeks by daily gavage at doses of 100, 200, or 300 mg kg-1 body weight per day (n = 10 mice per dose). Control animals (n = 10) received the same weight-based volume of vehicle. Sexual behavior and testosterone levels in serum and interstitial tissue of testis were measured after the last administration of VAP. Furthermore, to investigate the mechanisms of how VAP affects sexual behavior and testosterone synthesis in vivo, the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), and 3β-hydroxysteroid dehydrogenase (3β-HSD) in Leydig cells was also measured by immunofluorescence staining and quantitative real-time PCR. As a result, VAP produced a significant improvement in the sexual function of these aging male mice. Serum testosterone level and intratesticular testosterone (ITT) concentration also increased in the VAP-treated groups. The expression of StAR, P450scc, and 3β-HSD was also found to be enhanced in the VAP-treated groups compared with the control group. Our results suggested that VAP was effective in improving sexual function in aging male mice. The effect of velvet antler on sexual function was due to the increased expression of several rate-limiting enzymes of testosterone synthesis (StAR, P450scc, and 3β-HSD) and the following promotion of testosterone synthesis in vivo.

  20. Intra-sexual competition alters the relationship between testosterone and ornament expression in a wild territorial bird.

    PubMed

    Martínez-Padilla, J; Pérez-Rodríguez, L; Mougeot, F; Ludwig, S; Redpath, S M

    2014-05-01

    In a reliable signalling system, individual quality is expected to mediate the costs associated with ornamental displays, with relatively lower costs being paid by individuals of higher quality. These relative costs should depend not only on individual quality, but also on levels of intra-sexual competition. We explored the current and delayed effects that testosterone implants have on bird ornamentation in populations with contrasted population densities, as a proxy for intra-sexual competition. In a replicated experiment, we manipulated testosterone in 196 yearling male red grouse Lagopus lagopus scoticus in autumn in populations of high and low levels of intra-sexual competition. Males were assigned to one of three exogenous testosterone (T) treatments: empty implants (T0), small T implants (T1) or larger T implants (T2). We monitored subsequent changes in testosterone levels, ornament size and carotenoid-based colouration, carotenoid levels and body condition from autumn to spring. Testosterone implants increased testosterone levels, comb redness and comb size, and decreased body condition but these effects depended on levels of intra-sexual competition. Specifically, T2-implanted birds increased testosterone levels and comb size more, and reduced body condition more, in populations where intra-sexual competition was low. In the following spring, testosterone levels of T2-treated birds kept increasing in populations where intra-sexual competition was high but not in populations where intra-sexual competition was low. Our results highlight that levels of intra-sexual competition alter the relationship between testosterone levels and ornament expression, influencing their condition-dependence; they also indicate that the outcome of standard hormone manipulation conducted in free-living animals vary depending on the population context.

  1. Testosterone replacement therapy and voiding dysfunction

    PubMed Central

    Baas, Wesley

    2016-01-01

    Testosterone replacement therapy (TRT) represents an increasing popular treatment option for men with late-onset hypogonadism (LOH). Because of unsubstantiated beliefs of testosterone’s effect on the prostate, the FDA has recently placed a warning on testosterone products, stating that TRT may worsen benign prostatic hyperplasia (BPH). Within this review article we have demonstrated the current understanding of the physiology of testosterone and its relationship with prostatic and lower urinary tract physiology. The current evidence suggests that not only does TRT not worsen lower urinary tract symptoms (LUTS), but that hypogonadism itself is an important risk factor for LUTS/BPH. PMID:28078221

  2. Testosterone modulates gene expression pathways regulating nutrient accumulation, glucose metabolism and protein turnover in mouse skeletal muscle.

    PubMed

    Haren, M T; Siddiqui, A M; Armbrecht, H J; Kevorkian, R T; Kim, M J; Haas, M J; Mazza, A; Kumar, Vijaya B; Green, M; Banks, W A; Morley, J E

    2011-02-01

    Testosterone regulates energy metabolism and skeletal muscle mass in males, but the molecular mechanisms are not fully understood. This study investigated the response of skeletal muscle to castration and testosterone replacement in 8-week-old male mice. Using microarray analyses of mRNA levels in gastrocnemius muscle, 91 genes were found to be negatively regulated by testosterone and 68 genes were positively regulated. The mRNA levels of the insulin signalling suppressor molecule Grb10 and the glycogen synthesis inhibitors, protein phosphatase inhibitor-1 and phosphorylase kinase-γ, were negatively regulated by testosterone. The insulin-sensitive glucose and amino acid transporters, Glut3 and SAT2, the lipodystrophy gene, Lpin1 and protein targeting to glycogen were positively regulated. These changes would be expected to increase nutrient availability and sensing within skeletal muscle, increase metabolic rate and carbohydrate utilization and promote glycogen accumulation. The observed positive regulation of atrogin-1 (Fbxo32) by testosterone could be explained by the phosphorylation of Akt and Foxo3a, as determined by Western blotting. Testosterone prevented the castration-induced increase in interleukin-1α, the decrease in interferon-γ and the atrophy of the levator ani muscle, which were all correlated with testosterone-regulated gene expression. These findings identify specific mechanisms by which testosterone may regulate skeletal muscle glucose and protein metabolism.

  3. Behavioral and physiological responses to experimentally elevated testosterone in female dark-eyed juncos (Junco hyemalis carolinensis).

    PubMed

    Zysling, Devin A; Greives, Timothy J; Breuner, Creagh W; Casto, Joseph M; Demas, Gregory E; Ketterson, Ellen D

    2006-08-01

    Testosterone mediates the expression of many fitness-related traits in male vertebrates and is thought to account for numerous sex differences in trait expression. Testosterone is also secreted by females; however, far less is known regarding its effects on female physiology and behavior. Using a bird species in which the effects of testosterone on males are well characterized, the dark-eyed junco (Junco hyemalis), we tested whether an increase in exogenous testosterone in females would alter the phenotypic expression of a suite of behavioral and physiological traits. We found that increased testosterone levels in female dark-eyed juncos led to decreased cell-mediated immune function and increased intrasexual aggression, hypothalamo-pituitary-adrenal (HPA) axis responsiveness, baseline corticosterone and corticosterone-binding globulin (CBG) levels. Furthermore, immunosuppression following testosterone implantation was negatively correlated with total and free testosterone but did not appear to be related to either total or free corticosterone. These results demonstrate that the phenotypic impact of elevated testosterone is not confined to males in dark-eyed juncos, and that the impact in adults can be similar in males and females. We discuss these results in the context of potential endocrine-immune interactions and the evolution of sexual dimorphism.

  4. Beyond testosterone cypionate: evidence behind the use of nandrolone in male health and wellness.

    PubMed

    Pan, Michael M; Kovac, Jason R

    2016-04-01

    Characterized by low serum testosterone levels and diverse symptoms, male hypogonadism is a common condition. Current medical treatment focuses on testosterone supplementation using multiple modalities such as injections, gels and pellets. Interestingly, while testosterone is considered an anabolic androgenic steroid, it has not been saddled with the social stigma that other, similar medications have. The goal of this review is to highlight an anabolic steroid, 19-nortestosterone (i.e., nandrolone, deca-durabolin) and illustrate prospective therapeutic applications for male health. Containing a chemical structure similar to testosterone, nandrolone has a higher myotrophic: androgenic ratio resulting in improved effects on muscle mass. Animal models have suggested application in the improvement of joint healing following rotator cuff repair. Minimal literature exists regarding the use of nandrolone and, as such, further human studies are required.

  5. Beyond testosterone cypionate: evidence behind the use of nandrolone in male health and wellness

    PubMed Central

    Pan, Michael M.

    2016-01-01

    Characterized by low serum testosterone levels and diverse symptoms, male hypogonadism is a common condition. Current medical treatment focuses on testosterone supplementation using multiple modalities such as injections, gels and pellets. Interestingly, while testosterone is considered an anabolic androgenic steroid, it has not been saddled with the social stigma that other, similar medications have. The goal of this review is to highlight an anabolic steroid, 19-nortestosterone (i.e., nandrolone, deca-durabolin) and illustrate prospective therapeutic applications for male health. Containing a chemical structure similar to testosterone, nandrolone has a higher myotrophic: androgenic ratio resulting in improved effects on muscle mass. Animal models have suggested application in the improvement of joint healing following rotator cuff repair. Minimal literature exists regarding the use of nandrolone and, as such, further human studies are required. PMID:27141449

  6. 7alpha-methyl-19-nortestosterone (MENT) vs testosterone in combination with etonogestrel implants for spermatogenic suppression in healthy men.

    PubMed

    Walton, Melanie J; Kumar, Narender; Baird, David T; Ludlow, Helen; Anderson, Richard A

    2007-01-01

    Testosterone with a progestogen can suppress spermatogenesis for contraception. The synthetic androgen 7alpha-methyl-19-nortestosterone (MENT) may offer advantages because it is resistant to 5alpha-reduction and is therefore less active at the prostate. This study aimed to investigate MENT implants in combination with etonogestrel on spermatogenesis, gonadotropins, and androgen-dependent tissues in comparison with a testosterone/etonogestrel regimen. Healthy men (n = 29) were recruited and randomized to receive 2 etonogestrel implants with either 600-mg testosterone pellets repeated every 12 weeks or 2 MENT implants for up to 48 weeks. Testosterone concentrations in the testosterone group remained in the normal range. Subjects with 2 MENT implants showed peak MENT levels at 4 weeks with testosterone concentrations of 2 nmol/L. Sperm concentrations fell rapidly to less than 1 x 10(6)/mL at 12 weeks in 8 of 10 subjects in the MENT group and 13 of 16 subjects in the testosterone group with equally suppressed gonadotropins. Thereafter, suppression was not maintained in the MENT group, and 6 men noted loss of libido. Fourteen men completed 48 weeks of testosterone treatment, and all became azoospermic. Hemoglobin concentrations rose, and high density lipoprotein-cholesterol (HDL-C) fell in both groups. The MENT group showed a fall in prostate-specific antigen with no change in bone mass. MENT with a progestogen can achieve rapid suppression of spermatogenesis similar to testosterone, but this promising result was not sustained due to a decline in MENT release from the implants. This dose of testosterone, compared with previous studies using a lower dose with a higher dose of etonogestrel, had nonreproductive side effects without any increase in spermatogenic suppression. These data indicate the importance of the doses of progestogen and testosterone for optimum spermatogenic suppression while minimizing side effects.

  7. Testosterone reduces cumulative burying in female Wistar rats with minimal participation of estradiol.

    PubMed

    Gutiérrez-García, Ana G; Contreras, Carlos M; Vásquez-Hernández, Diana I; Molina-Jiménez, Tania; Jacome-Jacome, Emma

    2009-10-01

    Testosterone exerts anxiolytic effects, but the participation of its aromatase metabolic product estradiol is controversial. Therefore, we used the defensive burying paradigm in female Wistar rats to explore testosterone's (1.0 mg/rat, s.c.) interactions with picrotoxin (a noncompetitive gamma-aminobutyric acid-A receptor [GABA(A)] antagonist; 1.0 mg/kg, i.p.), formestane (an aromatase inhibitor; 3.0 mg/rat, s.c.), and tamoxifen (an estrogen receptor-beta antagonist; 1.0 mg/kg, s.c.). Serum levels of testosterone, estradiol, and progesterone were determined in the same rats. Burying latency and locomotion did not significantly change. Systemic testosterone administration enhanced serum testosterone and estradiol levels and reduced defensive burying. This reduction in total burying was blocked by pretreatment with picrotoxin and tamoxifen, but not formestane. We conclude that testosterone produced anxiolytic-like effects in female rats that were mediated by actions at the GABA(A) receptor, with participation of the estradiol receptor-beta, rather than estradiol aromatization.

  8. Testosterone replacement attenuates mitochondrial damage in a rat model of myocardial infarction.

    PubMed

    Wang, Fengyue; Yang, Jing; Sun, Junfeng; Dong, Yanli; Zhao, Hong; Shi, Hui; Fu, Lu

    2015-05-01

    Testosterone can affect cardiovascular disease, but its effects on mitochondrial dynamics in the post-infarct myocardium remain unclear. To observe the effects of testosterone replacement, a rat model of castration-myocardial infarction (MI) was established by ligating the left anterior descending coronary artery 2 weeks after castration with or without testosterone treatment. Expression of mitochondrial fission and fusion proteins was detected by western blot and immunofluorescence 14 days after MI. Cardiac function, myocardial inflammatory infiltration and fibrosis, cardiomyocyte apoptosis, mitochondrial microstructure, and ATP levels were also assessed. Compared with MI rats, castrated rats showed aggravated mitochondrial and myocardial insults, including mitochondrial swelling and disordered arrangement; loss of cristae, reduced mitochondrial length; decreased ATP levels; cardiomyocyte apoptosis; and impaired cardiac function. Results of western blotting analyses indicated that castration downregulated peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1A) and mitofusin 2, but upregulated dynamin-related protein 1. The results were also supported by results obtained using immunofluorescence. However, these detrimental effects were reversed by testosterone supplementation, which also elevated the upstream AMP-activated protein kinase (AMPK) activation of PGC1A. Thus, testosterone can protect mitochondria in the post-infarct myocardium, partly via the AMPK-PGC1A pathway, thereby decreasing mitochondrial dysfunction and cardiomyocyte apoptosis. The effects of testosterone were confirmed by the results of ELISA analyses.

  9. Activity Exerted by a Testosterone Derivative on Myocardial Injury Using an Ischemia/Reperfusion Model

    PubMed Central

    Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Elodia, García-Cervera; Eduardo, Pool-Gómez; Maria, López-Ramos; Marcela, Rosas-Nexticapa; Lenin, Hau-Heredia; Betty, Sarabia-Alcocer; Monica, Velázquez-Sarabia Betty

    2014-01-01

    Some reports indicate that several steroid derivatives have activity at cardiovascular level; nevertheless, there is scarce information about the activity exerted by the testosterone derivatives on cardiac injury caused by ischemia/reperfusion (I/R). Analyzing these data, in this study, a new testosterone derivative was synthetized with the objective of evaluating its effect on myocardial injury using an ischemia/reperfusion model. In addition, perfusion pressure and coronary resistance were evaluated in isolated rat hearts using the Langendorff technique. Additionally, molecular mechanism involved in the activity exerted by the testosterone derivative on perfusion pressure and coronary resistance was evaluated by measuring left ventricular pressure in the absence or presence of the following compounds: flutamide, prazosin, metoprolol, nifedipine, indomethacin, and PINANE TXA2. The results showed that the testosterone derivative significantly increases (P = 0.05) the perfusion pressure and coronary resistance in isolated heart. Other data indicate that the testosterone derivative increases left ventricular pressure in a dose-dependent manner (0.001–100 nM); however, this phenomenon was significantly inhibited (P = 0.06) by indomethacin and PINANE-TXA2  (P = 0.05) at a dose of 1 nM. In conclusion, these data suggest that testosterone derivative induces changes in the left ventricular pressure levels through thromboxane receptor activation. PMID:24839599

  10. Effects of orchidectomy and testosterone replacement on mouse pyrrolidone carboxypeptidase activity in the HPA axis.

    PubMed

    García-López, M J; Martínez-Martos, J M; Mayas, M D; Carrera, M P; Ramírez-Expósito, M J

    2004-03-01

    Pyrrolidone carboxypeptidase, also known as pyroglutamyl aminopeptidase, removes pyroglutamyl terminal residues from biologically active peptides such as thyrotropin-releasing hormone. The aim of the present work was to study the influence of orchidectomy and testosterone replacement on soluble (pyrrolidone carboxypeptidase type I) and membrane-bound (pyrrolidone carboxypeptidase type II) activities in the hypothalamus-pituitary-adrenal axis. Forty male mice (Balb/C) were distributed into five groups: sham-operated controls, orchidectomized, and orchidectomized treated with increasing doses of testosterone in each group (3, 6 and 12 mg/kg). In the hypothalamus, orchidectomy increased pyrrolidone carboxypeptidase type I, whereas the highest dose of testosterone returned this activity to control levels. In the pituitary, neither pyrrolidone carboxypeptidase type I nor type II activities changed after orchidectomy, although both activities increased after administration of testosterone in both cases. On the other hand, orchidectomy increased pyrrolidone carboxypeptidase type I and type II activities in adrenal glands, while testosterone replacement returned it to control levels. These results suggest that testosterone differentially modulates pyrrolidone carboxypeptidase type I and type II activities, and therefore also their endogenous substrate regulation. Thus, the influence of sex hormones in the physiology of the HPA axis through the modulation of the Pyrrolidone carboxypeptidase type I and type II activities is of great importance on stress and neuropathology associated with HPA dysfunction

  11. Enclomiphene, an estrogen receptor antagonist for the treatment of testosterone deficiency in men.

    PubMed

    Hill, Simon; Arutchelvam, Vijayaraman; Quinton, Richard

    2009-02-01

    Enclomiphene (Androxal), in development by Repros Therapeutics Inc, is a non-steroidal estrogen receptor antagonist that promotes gonadotropin-dependent testosterone secretion by the testes. Enclomiphene constitutes the trans-stereoisomer of clomiphene citrate, a drug that has been widely prescribed for several decades for the treatment of female ovulatory dysfunction. Because of the antagonistic effects of enclomiphene, the drug has the potential to increase serum testosterone levels in men with secondary hypogonadism by restoring physiological endogenous testosterone secretion while maintaining testicular volume and, potentially, spermatogenesis. In clinical trials conducted to date, enclomiphene demonstrated significant efficacy in the physiological restoration of testosterone levels in males with secondary hypogonadism. The compound also exhibited an unanticipated favorable effect on fasting plasma glucose; this result has been accompanied by rapidly accumulating evidence from other researchers for a bidirectional relationship between low serum testosterone and obesity/metabolic syndrome (syndrome X) in men. Short-term clinical safety data for enclomiphene have been satisfactory and equivalent to safety data for testosterone gels and placebo. Enclomiphene demonstrates promise in the management of secondary hypogonadism associated with obesity, metabolic syndrome and, possibly, infertility, and should undergo placebo-controlled, randomized clinical trials for these indications.

  12. Preventive effect of Pueraria mirifica on testosterone-induced prostatic hyperplasia in Sprague Dawley rats.

    PubMed

    Masrudin, S S; Mohamad, J

    2015-12-01

    Pueraria mirifica (PM) extract contains phytoestrogen daidzein and genistein. In this study, we investigated the protective effect of PM extract, daidzein and genistein on a testosterone-induced prostatic hyperplasia in rats. Testosterone was administered at 3 mg kg(-1) to rats followed by the PM extract, daidzein and genistein for a period of 30 days with finasteride as positive control. The testosterone level was increased, indicating inhibition of 5α-reductase converting testosterone to dihydrotestosterone. This was confirmed by prostate-specific antigen level that significantly decreased when treated with PM extract, daidzein and genistein. The PM extract, daidzein and genistein reduced the increase in the prostate/body weight ratio in testosterone-induced rats. This gives indication that PM extract, daidzein and genistein possessed protective activity for the treatment of benign prostatic hyperplasia. The analysis of histoarchitechture of the prostate has also shown that there was a significant improvement in prostatic cells of the testosterone-induced rats when treated with PM extract, daidzein and genistein.

  13. Activity exerted by a testosterone derivative on myocardial injury using an ischemia/reperfusion model.

    PubMed

    Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Elodia, García-Cervera; Eduardo, Pool-Gómez; Maria, López-Ramos; Marcela, Rosas-Nexticapa; Lenin, Hau-Heredia; Betty, Sarabia-Alcocer; Monica, Velázquez-Sarabia Betty

    2014-01-01

    Some reports indicate that several steroid derivatives have activity at cardiovascular level; nevertheless, there is scarce information about the activity exerted by the testosterone derivatives on cardiac injury caused by ischemia/reperfusion (I/R). Analyzing these data, in this study, a new testosterone derivative was synthetized with the objective of evaluating its effect on myocardial injury using an ischemia/reperfusion model. In addition, perfusion pressure and coronary resistance were evaluated in isolated rat hearts using the Langendorff technique. Additionally, molecular mechanism involved in the activity exerted by the testosterone derivative on perfusion pressure and coronary resistance was evaluated by measuring left ventricular pressure in the absence or presence of the following compounds: flutamide, prazosin, metoprolol, nifedipine, indomethacin, and PINANE TXA2. The results showed that the testosterone derivative significantly increases (P = 0.05) the perfusion pressure and coronary resistance in isolated heart. Other data indicate that the testosterone derivative increases left ventricular pressure in a dose-dependent manner (0.001-100 nM); however, this phenomenon was significantly inhibited (P = 0.06) by indomethacin and PINANE-TXA2  (P = 0.05) at a dose of 1 nM. In conclusion, these data suggest that testosterone derivative induces changes in the left ventricular pressure levels through thromboxane receptor activation.

  14. The association of testosterone, sleep, and sexual function in men and women.

    PubMed

    Andersen, Monica L; Alvarenga, Tathiana F; Mazaro-Costa, Renata; Hachul, Helena C; Tufik, Sergio

    2011-10-06

    Testosterone has been the focus of several investigations and review studies in males, but few have addressed its effects on sleep and sexual function, despite evidence of its androgenic effects on circadian activity in both sexes. Studies have been conducted to understand how sleeping increases (and how waking decreases) testosterone levels and how this rhythm can be related to sexual function. This review addresses the inter-relationships among testosterone, sexual function and sleep, including sleep-disordered breathing in both sexes, specifically its effects related to sleep deprivation. In addition, hormonal changes in testosterone that occur in the gonadal and adrenal axis with obstructive sleep apnea and other conditions of chronic sleep deprivation, and which consequently affect sexual life, have also been explored. Nevertheless, hormone-associated sleep disruptions occur across a lifetime, particularly in women. The association between endogenous testosterone and sex, sleep and sleep disturbances is discussed, including the results of clinical trials as well as animal model studies. Evidence of possible pathophysiological mechanisms underlying this relationship is also described. Unraveling the associations of sex steroid hormone concentrations with sleep and sexual function may have clinical implications, as sleep loss reduces testosterone levels in males, and low sex steroid hormone concentrations have been associated with sexual dysfunction.

  15. Direct radioimmunoassay (RIA) of salivary testosterone: correlation with free and total serium testosterone

    SciTech Connect

    Vittek, J.; L'Hommedieu, D.G.; Gordon, G.G.; Rappaport, S.C.; Southren, A.L.

    1985-08-26

    Simple and sensitive direct RIA for determination of salivary testosterone was developed by using RSL NOSOLVEX TM (125 1) kit produced by Radioassay System Laboratories (Carcon, California). In addition, a relationship between salivary and serum free and total testosterone concentrations was studied in randomly selected 45 healthy subjects, 5 females on oral contraceptive pills and 28 hypertensive patients on various treatment regimens. The lowest weight of testosterone detectable by the modified method was equivalent to 1 pg/ml of saliva, taking into account analytical variability. Intra- and interassay coefficients of variation were 5.09 +/- 2.7% and 8.2 +/- 5.9% respectively. Statistically significant correlations were found between salivary and serum free testosterone (r = 0.97) and salivary and serum total testosterone concentrations (r = 0.70 - 0.87). The exception to this was a group of hypertensive females in which no correlation (r = 0.14) between salivary and total serum testosterone was found. It is also of interest that, while salivary testosterone was significantly increased in subjects taking oral contraceptives and most of the hypertensive patients, the total serum testosterone concentration was in normal range. These findings suggest that the determination of salivary testosterone is a reliable method to detect changes in the concentration of available biologically active hormone in the circulation. 21 references, 4 figures, 1 table.

  16. Bioavailability: implications for science/cleanup policy

    SciTech Connect

    Denit, Jeffery; Planicka, J. Gregory

    1998-12-01

    This paper examines the role of bioavailability in risk assessment and cleanup decisions. Bioavailability refers to how chemicals ''behave'' and their ''availability'' to interact with living organisms. Bioavailability has significant implications for exposure risks, cleanup goals, and site costs. Risk to human health and the environment is directly tied to the bioavailability of the chemicals of concern.

  17. Zinc bioavailability in the chick

    SciTech Connect

    Hempe, J.M.

    1987-01-01

    Methods for assessing zinc bioavailability were evaluated in the chick. A low-zinc chick diet was developed using rehydrated, spray-dried egg white autoclaved at 121 C for 30 min as the primary protein source. The relative bioavailability of zinc from soy flour and beef was determined by whole-body retention of extrinsic /sup 65/Zn, and in slope ratio assays for growth rate and tissue zinc. Compared to zinc carbonate added to an egg white-based diet, all methods gave similar estimates of approximately 100% zinc bioavailability for beef but estimates for soy flour varied widely. The slope ratio assay for growth rate gave the best estimate of zinc bioavailability for soy flour. True absorption, as measured by percent isotope retention from extrinsically labeled soy flour, was 47%.

  18. TV Ads Help Drive Testosterone Supplement Sales

    MedlinePlus

    ... examined the ratings of these advertisements in 75 market areas across the United States, and compared them ... 2 million men with private insurance in those markets had themselves tested for low testosterone, while more ...

  19. Testosterone abolishes implicit subordination in social anxiety.

    PubMed

    Terburg, David; Syal, Supriya; Rosenberger, Lisa A; Heany, Sarah J; Stein, Dan J; Honk, Jack van

    2016-10-01

    Neuro-evolutionary theories describe social anxiety as habitual subordinate tendencies acquired through a recursive cycle of social defeat and submissive reactions. If so, the steroid hormone testosterone might be of therapeutic value, as testosterone is a main force behind implicit dominance drive in many species including humans. We combined these two theories to investigate whether the tendency to submit to the dominance of others is an implicit mechanism in social anxiety (Study-1), and whether this can be relieved through testosterone administration (Study-2). Using interactive eye-tracking we demonstrate that socially anxious humans more rapidly avert gaze from subliminal angry eye contact (Study-1). We replicate this effect of implicit subordination in social anxiety in an independent sample, which is subsequently completely abolished after a single placebo-controlled sublingual testosterone administration (Study-2). These findings provide crucial evidence for hormonal and behavioral treatment strategies that specifically target mechanisms of dominance and subordination in social anxiety.

  20. Testosterone enhancement of thyroid carcinoma in rats: the role of TSH

    SciTech Connect

    Hofmann, C.; Oslapas, R.; Nayyar, R.; McCall, A.; Paloyan, E.

    1986-12-01

    Radiation treatment of Long-Evans male rats (40 mu Ci Na131I at the age of 2 months) led to a high incidence of thyroid follicular carcinomas at the age of 24 months; castration of males before irradiation caused a significant reduction in incidence of this tumor. In this study, replacement testosterone (T) was administered to castrated male rats by means of implanted, slow-release hormone-containing pellets (T-physiologic dose). Three testosterone doses (0.1T, 1.0T, and 30T) were used to treat groups of castrated irradiated and castrated nonirradiated rats from 2 to 18 months of age. The incidence of thyroid follicular carcinoma at 18 months in irradiated rats depended on the dose of replacement testosterone used. Tumor incidence was 8%, 14%, 41%, and 50% after treatment with 0T, 0.1T, 1.0T, and 30T, respectively. The incidence of thyroid follicular carcinoma in nonirradiated rats ranged from 0 to 7%. Mean serum thyroid-stimulating hormone (TSH) values in irradiated animal groups were elevated significantly above those for age-matched nonirradiated animals. The degree of TSH elevation in irradiated animals was related directly to the testosterone-replacement level. All rat groups showed age-dependent decreases in serum T4 levels, and T4 levels were also lowered by replacement testosterone in nonirradiated castrated animals. In aging irradiated animals, serum T4 levels were similarly decreased by testosterone, despite elevated TSH levels in these groups. In this study, testosterone appeared to act indirectly to promote development of irradiation-induced thyroid tumors by early and prolonged elevation of TSH levels.

  1. Consequences of elevating plasma testosterone in females of a socially monogamous songbird: evidence of constraints on male evolution?

    PubMed

    Clotfelter, Ethan D; O'Neal, Dawn M; Gaudioso, Jacqueline M; Casto, Joseph M; Parker-Renga, Ian M; Snajdr, Eric A; Duffy, Deborah L; Nolan, Val; Ketterson, Ellen D

    2004-08-01

    To explore whether selection for testosterone-mediated traits in males might be constrained by costs of higher testosterone to females, we examined the effects of experimental elevation of plasma testosterone on physiological, reproductive, and behavioral parameters in a female songbird, the dark-eyed junco (Junco hyemalis). We used subcutaneous implants to elevate testosterone (T) in captive and free-living female juncos. In captive birds, we measured the effects of high T on body mass, feather molt, and brood patch formation. In the field, we monitored its effects on the timing of egg laying, clutch size, egg size, egg steroid levels, incubation, and nest-defense behavior. Females implanted with testosterone (T-females) had significantly higher circulating levels of testosterone than did control females (C-females). Captive T-females had lower body mass, were less likely to develop brood patches, and delayed feather molt relative to C-females. Among free-living females, the interval between nest completion and appearance of the first egg was longer for T-females than for C-females and egg yolk concentrations of testosterone were higher, but there were no significant differences in estradiol levels, clutch size, or egg size. Incubation and nest defense behavior were also similar between T- and C-females. Our results suggest that selection on males for higher testosterone might initially lead to a correlated response in females producing changes in body mass and feather molt, both of which could be detrimental. Other possible female responses would be delayed onset of reproduction, which might reduce reproductive success, and higher yolk testosterone, which might have either positive or negative effects on offspring development. We found no reason to expect reduced parental behavior by females as a negative fitness consequence of selection for higher testosterone in males.

  2. Effects of aromatase inhibition vs. testosterone in older men with low testosterone: randomized-controlled trial.

    PubMed

    Dias, J P; Melvin, D; Simonsick, E M; Carlson, O; Shardell, M D; Ferrucci, L; Chia, C W; Basaria, S; Egan, J M

    2016-01-01

    Aging in men is associated with loss of bone mass, impaired physical function and altered body composition. The objective of this proof-of-concept randomized, double-blind, placebo-controlled, parallel-group, single-center trial was to determine the relative effects of testosterone (T) and estradiol (E(2)) on bone mineral density, body composition, and physical performance in older men. The primary outcome was lumbar spine bone mineral density (BMD), and secondary outcomes were body composition, muscle strength, gait speed, and sex hormone concentrations. Forty three men (age range, 65-82 years; mean age 71 years) with low total T levels <350 ng/dL were randomized to one of three groups: 5 g transdermal testosterone gel (TT) (N = 16), anastrozole (AI) 1 mg (N = 14) or placebo daily (N = 13) for 12 months. Outcomes were assessed at baseline, 3, 6, and 12 months. Both TT and AI increased serum TT levels (>500 ng/dL, p < 0.05) compared to baseline; T values remained stable throughout the duration of the trial. At 12 months, TT improved the primary outcome of lumbar spine BMD (p < 0.01).Both interventions improved knee strength at 12 months compared to baseline (p < 0.05) while lean body mass significantly increased only in the AI group at 6 and 12 months (1.49 ± 0.38 kg, p < 0.01; 1.24 ± 0.39 kg, p < 0.05, respectively) compared to baseline. Interestingly, TT improved fast gait speed at 3 and 12 months (p < 0.01, p < 0.05, respectively). In summary, this proof-of-concept study confirms that aromatization of T is required for maintaining BMD in older men with low-T levels. The trial also uncovered the novel finding that aromatization of T is required for improvement in fast gait speed, an observation that needs to be verified in future studies.

  3. REDD1 Is a Major Target of Testosterone Action in Preventing Dexamethasone-Induced Muscle Loss

    PubMed Central

    Wu, Yong; Zhao, Weidong; Zhao, Jingbo; Zhang, Yuanfei; Qin, Weiping; Pan, Jiangping; Bauman, William A.; Blitzer, Robert D.; Cardozo, Christopher

    2010-01-01

    Glucocorticoids are a well-recognized and common cause of muscle atrophy that can be prevented by testosterone. However, the molecular mechanisms underlying such protection have not been described. Thus, the global effects of testosterone on dexamethasone-induced changes in gene expression were evaluated in rat gastrocnemius muscle using DNA microarrays. Gene expression was analyzed after 7-d administration of dexamethasone, dexamethasone plus testosterone, or vehicle. Dexamethasone changed expression of 876 probe sets by at least 2-fold. Among these, 474 probe sets were changed by at least 2-fold in the opposite direction in the dexamethasone plus testosterone group (genes in opposition). Major biological themes represented by genes in opposition included IGF-I signaling, myogenesis and muscle development, and cell cycle progression. Testosterone completely prevented the 22-fold increase in expression of the mammalian target of rapamycin (mTOR) inhibitor regulated in development and DNA damage responses 1 (REDD1), and attenuated dexamethasone induced increased expression of eIF4E binding protein 1, Forkhead box O1, and the p85 regulatory subunit of the IGF-I receptor but prevented decreased expression of IRS-1. Testosterone attenuated increases in REDD1 protein in skeletal muscle and L6 myoblasts and prevented dephosphorylation of p70S6 kinase at the mTOR-dependent site Thr389 in L6 myoblast cells. Effects of testosterone on REDD1 mRNA levels occurred within 1 h, required the androgen receptor, were blocked by bicalutamide, and were due to inhibition of transcriptional activation of REDD1 by dexamethasone. These data suggest that testosterone blocks dexamethasone-induced changes in expression of REDD1 and other genes that collectively would otherwise down-regulate mTOR activity and hence also down-regulate protein synthesis. PMID:20032058

  4. Testosterone Administration Related Differences in Brain Activation during the Ultimatum Game

    PubMed Central

    Kopsida, Eleni; Berrebi, Jonathan; Petrovic, Predrag; Ingvar, Martin

    2016-01-01

    A plethora of studies on the Ultimatum Game have shown that responders forfeit the rule of profit maximization and punish unfair proposers, by rejecting their offers. This behavior has been linked to increased amygdala, insula, and dorsolateral prefrontal cortex activation. Studies have suggested a potential role of testosterone in the Ultimatum Game albeit with inconsistent findings. In the present study, we sought to further investigate the role of amygdala and testosterone in the Ultimatum Game, by conducting a double-blinded, single-administration study. Sixty milligram of Tostrex was administered to male and female healthy volunteers, 3 h prior to undergoing an fMRI session, during which they played a standard version of the Ultimatum Game. The behavioral analysis revealed a statistical trend, as participants in the testosterone group tended to accept a greater number of unfair offers than participants in the placebo group, irrespectively of gender. In terms of fMRI results, for the main contrast unfair>fair offers, the testosterone group displayed a greater activation in the right dlPFC compared to the placebo group. Increased testosterone levels were related to greater caudate activity. Our findings suggest a complex role of testosterone in social behavior and decision-making. PMID:26973448

  5. Hormones and honest signals: males with larger ornaments elevate testosterone more when challenged.

    PubMed

    McGlothlin, J W; Jawor, J M; Greives, T J; Casto, J M; Phillips, J L; Ketterson, E D

    2008-01-01

    When male investment in mating varies with quality, reliable sexual signals may evolve. In many songbirds, testosterone mediates mating investment, suggesting that signals should be linked to testosterone production. However, because testosterone may change rapidly during behaviour such as territorial aggression and courtship, efforts to establish such a relationship have proved challenging. In a population of dark-eyed juncos, we measured individual variation in the production of short-term testosterone increases by injecting gonadotropin-releasing hormone (GnRH). We found a positive correlation between the magnitude of these increases and the size of a plumage ornament ('tail white') previously shown to be important for female choice and male-male competition. We then measured naturally elevated testosterone levels produced during male-male competition and found that they covaried with those induced by GnRH. We suggest that the association between tail white and testosterone increases may allow conspecifics to assess potential mates and competitors reliably using tail white.

  6. Endogenous Testosterone Modulates Prefrontal–Amygdala Connectivity during Social Emotional Behavior

    PubMed Central

    Toni, Ivan; Verhagen, Lennart; Roelofs, Karin

    2011-01-01

    It is clear that the steroid hormone testosterone plays an important role in the regulation of social emotional behavior, but it remains unknown which neural circuits mediate these hormonal influences in humans. We investigated the modulatory effects of endogenous testosterone on the control of social emotional behavior by applying functional magnetic resonance imaging while healthy male participants performed a social approach–avoidance task. This task operationalized social emotional behavior by having participants approach and avoid emotional faces by pulling and pushing a joystick, respectively. Affect-congruent trials mapped the automatic tendency to approach happy faces and avoid angry faces. Affect-incongruent trials required participants to override those automatic action tendencies and select the opposite response (approach-angry, avoid-happy). The social emotional control required by affect-incongruent responses resulted in longer reaction times (RTs) and increased activity at the border of the ventrolateral prefrontal cortex and frontal pole (VLPFC/FP). We show that endogenous testosterone modulates these cerebral congruency effects through 2 mechanisms. First, participants with lower testosterone levels generate larger VLPFC/FP responses during affect-incongruent trials. Second, during the same trials, endogenous testosterone modulates the effective connectivity between the VLPFC/FP and the amygdala. These results indicate that endogenous testosterone influences local prefrontal activity and interregional connectivity supporting the control of social emotional behavior. PMID:21339377

  7. Selenium in soybeans: bioavailability and form

    SciTech Connect

    Mason, A.C.

    1984-01-01

    Experiments are presented which evaluate the bioavailability of different forms of selenium from intrinsically and extrinsically labeled isolated soy protein and soy flour. The bioavailability of selenium from soy and egg is compared and some characteristics of selenium are described as it exists in soybeans. The metabolism of selenium was measured by whole-body and tissue radioactivity retention and selenium excretion. Selenium-75 was well absorbed from an isolated soy protein diet by rats. Selenium-75 from isolated soy protein labeled intrinsically and extrinsically with /sup 75/Se selenate was better absorbed than from protein labeled extrinsically with /sup 75/Se selenite or /sup 75/Se selenomethionine. Bioavailability of selenium from soy flour and egg was measured by whole-body and tissue radioactivity retention and glutathione peroxidase (GSH-Px) activity regeneration. Selenium-75 from soy flour intrinsically labeled with selenite was better absorbed than /sup 75/Se from flour intrinsically labeled with selenate. GSH-Px levels in the liver, kidney, platelets and heart fell when rats were fed a selenium deficient diet, but were not significantly raised on 0.0825 ppm Se repletion diets.

  8. Successful hunting increases testosterone and cortisol in a subsistence population.

    PubMed

    Trumble, Benjamin C; Smith, Eric A; O'Connor, Kathleen A; Kaplan, Hillard S; Gurven, Michael D

    2014-02-07

    Controversy over the adaptive significance of male hunting in subsistence societies hinges on the relative importance of familial provisioning and mate-quality signalling. This paper examines the proximate and ultimate motivations of hunting behaviour from a neuroendocrine perspective, using salivary testosterone and cortisol data collected before, during and after hunting focal follows from 31 Tsimane hunters aged 18-82 years. Despite circadian declines in hormone levels, testosterone and cortisol of Tsimane hunters increased at the time of a kill, and remained high as successful hunters returned home. Previous studies of hormonal changes during competitions find that high-stakes and success in the presence of relevant audiences result in increased neuroendocrine arousal. If men hunt primarily to provision their families, then an additional audience would not be expected to impact testosterone or cortisol, nor would the size of the animal killed. However, if signalling male quality by 'showing off' was a larger relative driver of men's hunting behaviour, one would expect greater hormonal response in cases where men returned with large sharable kills, especially in the presence of community members. Consistent with provisioning models of male hunting motivation, neither kill size nor encountering an audience of villagers while returning from hunting was associated with hormonal changes for successful hunters.

  9. Successful hunting increases testosterone and cortisol in a subsistence population

    PubMed Central

    Trumble, Benjamin C.; Smith, Eric A.; O'Connor, Kathleen A.; Kaplan, Hillard S.; Gurven, Michael D.

    2014-01-01

    Controversy over the adaptive significance of male hunting in subsistence societies hinges on the relative importance of familial provisioning and mate-quality signalling. This paper examines the proximate and ultimate motivations of hunting behaviour from a neuroendocrine perspective, using salivary testosterone and cortisol data collected before, during and after hunting focal follows from 31 Tsimane hunters aged 18–82 years. Despite circadian declines in hormone levels, testosterone and cortisol of Tsimane hunters increased at the time of a kill, and remained high as successful hunters returned home. Previous studies of hormonal changes during competitions find that high-stakes and success in the presence of relevant audiences result in increased neuroendocrine arousal. If men hunt primarily to provision their families, then an additional audience would not be expected to impact testosterone or cortisol, nor would the size of the animal killed. However, if signalling male quality by ‘showing off’ was a larger relative driver of men's hunting behaviour, one would expect greater hormonal response in cases where men returned with large sharable kills, especially in the presence of community members. Consistent with provisioning models of male hunting motivation, neither kill size nor encountering an audience of villagers while returning from hunting was associated with hormonal changes for successful hunters. PMID:24335989

  10. Modulating testosterone pathway: a new strategy to tackle male skin aging?

    PubMed Central

    Bernard, Philippe; Scior, Thomas; Do, Quoc Tuan

    2012-01-01

    In men, the level of testosterone decreases with age. At the skin level, the result is observed as a decrease in density and in a lower elasticity. Identifying compounds that are able to increase the level of testosterone appears to be an attractive strategy to develop new antiaging bioactive ingredients for men. Reverse pharmacognosy was successfully applied to identify new natural compounds able to modulate testosterone levels. Among several in silico hits, honokiol was retained as a candidate as it has the greatest potential to become an active ingredient. This result was then validated in vitro on aromatase and 5-alpha-reductase type 1 and 2, which are two types of enzymes implicated in the degradation of free testosterone. Indeed, honokiol was identified as an inhibitor of aromatase, with a half-maximal inhibitory concentration (IC50) of about 50 μM. In addition, honokiol was shown to be an inhibitor of 5-alpha-reductase type 1, with an IC50 of about 75 μM. Taken together, these data indicate that honokiol modulates testosterone levels, and its structure has the potential to serve as a lead for future designs of highly selective inhibitors of 5-alpha-reductase type 1. PMID:23049247

  11. Modulating testosterone pathway: a new strategy to tackle male skin aging?

    PubMed

    Bernard, Philippe; Scior, Thomas; Do, Quoc Tuan

    2012-01-01

    In men, the level of testosterone decreases with age. At the skin level, the result is observed as a decrease in density and in a lower elasticity. Identifying compounds that are able to increase the level of testosterone appears to be an attractive strategy to develop new antiaging bioactive ingredients for men. Reverse pharmacognosy was successfully applied to identify new natural compounds able to modulate testosterone levels. Among several in silico hits, honokiol was retained as a candidate as it has the greatest potential to become an active ingredient. This result was then validated in vitro on aromatase and 5-alpha-reductase type 1 and 2, which are two types of enzymes implicated in the degradation of free testosterone. Indeed, honokiol was identified as an inhibitor of aromatase, with a half-maximal inhibitory concentration (IC(50)) of about 50 μM. In addition, honokiol was shown to be an inhibitor of 5-alpha-reductase type 1, with an IC(50) of about 75 μM. Taken together, these data indicate that honokiol modulates testosterone levels, and its structure has the potential to serve as a lead for future designs of highly selective inhibitors of 5-alpha-reductase type 1.

  12. Testosterone replacement therapy and the heart: friend, foe or bystander?

    PubMed Central

    Canfield, Steven; Wang, Run

    2016-01-01

    The role of testosterone therapy (TTh) in cardiovascular disease (CVD) outcomes is still controversial, and it seems will remain inconclusive for the moment. An extensive body of literature has investigated the association of endogenous testosterone and use of TTh with CVD events including several meta-analyses. In some instances, a number of studies reported beneficial effects of TTh on CVD events and in other instances the body of literature reported detrimental effects or no effects at all. Yet, no review article has scrutinized this body of literature using the magnitude of associations and statistical significance reported from this relationship. We critically reviewed the previous and emerging body of literature that investigated the association of endogenous testosterone and use of TTh with CVD events (only fatal and nonfatal). These studies were divided into three groups, “beneficial (friendly use)”, “detrimental (foe)” and “no effects at all (bystander)”, based on their magnitude of associations and statistical significance from original research studies and meta-analyses of epidemiological studies and of randomized controlled trials (RCT’s). In this review article, the studies reporting a significant association of high levels of testosterone with a reduced risk of CVD events in original prospective studies and meta-analyses of cross-sectional and prospective studies seems to be more consistent. However, the number of meta-analyses of RCT’s does not provide a clear picture after we divided it into the beneficial, detrimental or no effects all groups using their magnitudes of association and statistical significance. From this review, we suggest that we need a study or number of studies that have the adequate power, epidemiological, and clinical data to provide a definitive conclusion on whether the effect of TTh on the natural history of CVD is real or not. PMID:28078222

  13. Influx of testosterone-binding globulin (TeBG) and TeBG-bound sex steroid hormones into rat testis and prostate

    SciTech Connect

    Sakiyama, R.; Pardridge, W.M.; Musto, N.A.

    1988-07-01

    The availability of testosterone and estradiol to Sertoli and prostate cells is dependent upon 1) the permeability properties of the blood-tubular barrier (BTB) of the testis or prostate cell membrane, and 2) sex steroid binding to plasma proteins, such as albumin or testosterone-binding globulin (TeBG). Sex steroid influx into these tissues was studied after in vivo arterial bolus injections of (/sup 3/H)testosterone or (/sup 3/H)estradiol in anesthetized rats. Both testosterone and estradiol were readily cleared across the BTB or prostate cell membrane in the absence of plasma proteins and in the presence of human pregnancy serum, in which testosterone or estradiol are 80-95% distributed to TeBG. The extravascular extraction of (/sup 3/H)TeBG across the BTB or prostate plasma membrane (73 +/- 2% (+/- SE) and 92 +/- 9%, respectively) was significantly greater than extraction of (/sup 3/H)albumin or other plasma space markers and indicative of a rapid first pass clearance of TeBG by Sertoli or prostate cells. In summary, these studies indicate that 1) testosterone and estradiol are readily cleared by Sertoli and prostate cells; 2) albumin- and TeBG-bound sex steroids represent the major circulating pool of bioavailable hormone for testis or prostate; and 3) the TeBG-sex steroid complex may be nearly completely available for influx through the BTB or prostate plasma membrane.

  14. Testosterone concentrations in female athletes and ballet dancers with menstrual disorders.

    PubMed

    Łagowska, Karolina; Kapczuk, Karina

    2016-01-01

    Menstrual disorders are common among female athletes and ballet dancers. Endocrine changes, such as high testosterone (HT) levels and high luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratios, may suggest functional ovarian hyperandrogenism which may induce such dysfunction. The aim of this study was therefore to evaluate endocrine status in female athletes and ballet dancers with menstrual disorders. Their nutritional status and dietary habits were analysed in relation to the testosterone levels. In a cross-sectional approach, 31 female athletes (18.1 ± 2.6 years) and 21 ballerinas (17.1 ± 0.9) with menstrual disorders participated in the study. The levels of serum LH, FSH, progesterone (P), estradiol (E2), prolactin (PRL), thyroid-stimulating hormone, testosterone (T) and sex hormone-binding globulinwere measured to assess hormonal status. In addition, the free androgen index (FAI) was calculated. Nutritional status, total daily energy expenditure and nutritional habits were evaluated. Girls were assigned to one of the following groups: low testosterone (LT) level, normal testosterone level or HT level. There were significant differences between ballerinas and other female athletes in terms of testosterone levels, FAI, age at the beginning of training, length of training period and age at menarche. The PRL level was lowest in the LT group while the FAI index was highest in the HT group. Daily energy and carbohydrate intakes were significantly lower in the HT group. T levels in the study subjects were found to be associated with nutritional factors, energy availability, age at the beginning of training and frequency of training. This is the first report of HT levels being associated with the status of a female ballet dancer, the age of menarche and the length of the training history. Further research is necessary to confirm the results in a larger study group.

  15. Alteration in sexually dimorphic testosterone biotransformation profiles as a biomarker of chemically induced androgen disruption in mice.

    PubMed Central

    Wilson, V S; McLachlan, J B; Falls, J G; LeBlanc, G A

    1999-01-01

    Assessment of the impact of environmental chemicals on androgen homeostasis in rodent models is confounded by high intraindividual and interindividual variability in circulating testosterone levels. Our goal was to evaluate changes in testosterone biotransformation processes as a measure of androgen homeostasis and as a biomarker of exposure to androgen-disrupting chemicals. Sex-specific differences in hepatic testosterone biotransformation enzyme activities were identified in CD-1 mice. Gonadectomy followed by replacement of individual steroid hormones identified specific sex differences in biotransformation profiles that were due to the inductive or suppressive effects of testosterone. Notably, significant androgen-dependent differences in testosterone 6[alpha]- and 15[alpha]-hydroxylase activities were demonstrated, and the ratio of 6[alpha]- and 15[alpha]-hydroxylase activities proved to be an excellent indicator of the androgen status within the animal. The male or "masculinized" testosterone 6[alpha]/15[alpha]-hydroxylase ratio was significantly less than the female or "feminized" ratio. Male mice were exposed to both an antiandrogen, vinclozolin, and to a compound that modulates serum androgen levels, indole-3-carbinol, to test the utility of this ratio as a biomarker of androgen disruption. Treatment with the antiandrogen vinclozolin significantly increased the 6[alpha]/15[alpha]-hydroxylase ratio. Indole-3-carbinol treatment resulted in a dose-dependent, but highly variable, decrease in serum testosterone levels. The 6[alpha]/15[alpha]-hydroxylase ratio increased as serum testosterone levels decreased in these animals. However, the increase in the ratio was much less variable and more sensitive than serum testosterone levels. These investigations demonstrate that the 6[alpha]/15[alpha]-hydroxylase ratio is a powerful measure of androgen modulation and a sensitive indicator of exposure to androgen-disrupting chemicals in CD-1 mice. Images Figure 1 Figure 2

  16. Monitoring testicular activity of male Eurasian (Lynx lynx) and Iberian (Lynx pardinus) lynx by fecal testosterone metabolite measurement.

    PubMed

    Jewgenow, K; Naidenko, S V; Goeritz, F; Vargas, A; Dehnhard, M

    2006-11-01

    (Eurasian lynx, r2=0.488; p<0.001; Iberian lynx, r2=0.85, p<0.0001). Thus, seasonal reproductive activity of male Eurasian lynx was demonstrated also by Immulite -assay, confirming high testosterone levels during breeding season in March/April as previously documented with EIA. Preliminary results on testosterone measurements in Iberian lynx feces confirmed the suitability of the applied Immulite test in this highly endangered species.

  17. Muscle specific miRNAs are induced by testosterone and independently upregulated by age

    PubMed Central

    Nielsen, Søren; Hvid, Thine; Kelly, Meghan; Lindegaard, Birgitte; Dethlefsen, Christine; Winding, Kamilla; Mathur, Neha; Scheele, Camilla; Pedersen, Bente K.; Laye, Matthew J.

    2014-01-01

    Age dependent decline in skeletal muscle function leads to impaired metabolic flexibility in elderly individuals. Physical activity and testosterone treatment have proven efficient strategies for delaying this condition. However, a common molecular pathway has not been identified. Muscle specific miRNAs (myomiRs) regulate metabolic pathways in skeletal muscle, are regulated by physical activity, and have response elements for testosterone in their promoter region. We therefore hypothesized that myomiRs would be regulated in skeletal muscle during aging. We further investigated any potential gender-dependent regulation of these miRNAs. We found that the myomiRs miR-1, miR-133a, and miR-133b were increased in skeletal muscle of elderly men compared to younger men. In addition, miR-133a/133b expression was markedly higher in women compared to men. Elimination of circulating testosterone in men was associated with lower levels of miR-133a and miR-133b. A positive regulatory effect of testosterone on miR-133a/133b expression was confirmed in castrated male C57BL/6J mice and in a model of primary human myocytes. Yet, an improvement of fitness level in the testosterone depleted men resulted in a down-regulation of miR133a/b. In conclusion, alterations in fitness level and circulating testosterone seem to represent two independent regulatory events where testosterone is a specific regulator of miR-133a/b expression. PMID:24478708

  18. A Testosterone-Related Structural Brain Phenotype Predicts Aggressive Behavior From Childhood to Adulthood

    PubMed Central

    Nguyen, Tuong-Vi; McCracken, James T; Albaugh, Matthew D; Botteron, Kelly N.; Hudziak, James J; Ducharme, Simon

    2015-01-01

    Structural covariance, the examination of anatomic correlations between brain regions, has emerged recently as a valid and useful measure of developmental brain changes. Yet the exact biological processes leading to changes in covariance, and the relation between such covariance and behavior, remain largely unexplored. The steroid hormone